Sabtu, 31 Juli 2010

An Erratic Fluctuation of the Vacuum Gauge During Idle

Vacuum gauges are among the mechanic's most useful but lesser known tools. Intake manifold vacuum has long been known as an indicator of load on the engine; more throttle and more load equals less vacuum, and vice versa for more vacuum. A fluctuating vacuum reading can mean a number of things, many of which will cause a noticeable power loss or misfire.

Slow, Wide Fluctuation

    A needle that fluctuates fairly slowly and over a wide range usually indicates a problem with either the carburetor adjustment or the engine's air and fuel management system. As vacuum rises, it sucks more fuel through the carburetor, throwing off the air-to-fuel ratio and causing a drop in manifold vacuum. The same thing might happen if you've got a bad throttle position, manifold air pressure or mass airflow sensor.

Quick, Short Fluctuations

    A vacuum reading that very quickly drops and rises a couple inches of mercury or psi generally indicates some sort of ignition system malfunction. You might have a misfire as the result of a bad coil or crossfiring in the distributor, or you may have a spark plug with too small or large a gap. If the needle is truly spastic, you could have a multicylinder ignition misfire. On a computer-controlled car, a bad cam or crank position sensor could cause this, but these will manifest in other and more noticeable ways.

Wide Fluctuation at Idle

    A wide fluctuation at idle generally means that something's gone awry between two of the engine's cylinders; one is pulling when it should be pushing, the other may be doing nothing. The only way this is going to happen is if you've either blown a head gasket or cranked the head, in which case you'll see other symptoms. You're likely to see excessive exhaust smoke that smells like fuel, antifreeze, oil or all three.

Low Reading

    Low and periodically fluctuating vacuum readings under all conditions is a classic indicator of worn piston rings or an engine in need of a rebuild. The worn rings or excessively large bore will allow combustion gases to escape into the crankcase and won't seal well enough to pull the standard vacuum. Additional symptoms include excessive crankcase pressure as a result of ring blow-by; you'll see this as a hot wind puffing out of your valve cover oil filler hole.

Valvetrain Problems

    A vacuum gauge needle that vibrates rapidly at idle and then seems to smooth out with rpm can indicate bad valve guides or a bad cam lobe. The bad guides allow the valve to move around a bit while the valves are at their lowest opening point, and the bad lobe will effectively kill that cylinder at low lift. Intermittent drops in vacuum at idle and under cruise could indicate a sticking valve, and needle drop of vibration under acceleration can indicate a bad valve or valveseat. Hydraulic lifter bleed-off will manifest as an intermittent vacuum drop at idle, and incorrect valve lash will mimic the effects of a bad valve.

Gauge Dampener

    Engine idle isn't a steady thing; it actually fluctuates regularly as the pistons suck in regular gulps of air. This is especially true on large displacement engines with a relatively low cylinder count, like a 500 cubic inch V-8 or a 300 cubic inch six cylinder. Vacuum gauges have dampeners inside to keep the needle from constantly vibrating, and those dampeners do wear out over time. Additionally, aftermarket vacuum gauges, particularly those designed for diagnosis as opposed to installation, may require a separate dampener to keep from giving a false reading under normal conditions.

Jumat, 30 Juli 2010

How to Troubleshoot a Deutz F6l912

How to Troubleshoot a Deutz F6l912

The Deutz F6l912 is an all purpose six-cylinder 5.6-liter diesel engine. It is an industrial motor and can be used in a variety of applications. This rugged engine is designed for hard, long use and is made to last. However any engine is only as good as it is treated. Regular maintenance will not only increase performance and keep the engine running its best, but also spot issues before they become major concerns.

Instructions

    1

    Troubleshoot the engine if it is failing to start. First make sure there is fresh oil and the right type of fuel in it. Check the fuel pump. A broken fuel unit can cause the engine to fail to start. Check if the fuel filter is clogged with debris, and clean it out or replace it if necessary. If there is be air in the fuel system, the solution is to bleed the lines. Check the injector lines and see if they are blocked and clean if necessary.

    2

    Check for performance issues. A number of issues could cause the engine to lose power or perform poorly. Inspect the tank vent to make sure that it is open. Check the connections on the fuel lines and injector lines and tighten, if necessary. Test the timing of the fuel pump and readjust if needed. If the injection nozzle is broken it must be replaced. Adjust the idle speed to a higher setting.

    3

    Check for other issues: Test the glow plugs if the pre-heating system is defective. Check if the delivery valve is leaking, and if it is, replace it. Check the bumper spring and adjust if necessary. If the engine compression is low or uneven then it will need repair.

Problems With Ball Joints

Ball joints serve, in a sense, as the connecting point between the suspension and the wheels. Suspected problems with ball joints should be investigated right away, because the worst-case scenario of complete ball joint failure could result in significant damage to other parts underneath the vehicle, as well as a risk of personal injury.

Loss of Lubrication

    This is a fairly common ball joint problem, as explained by the Automotive Diagnostic and Repair Help For Cars and Trucks website. Some types of ball joints, such as those found in older model vehicles, require regreasing as a standard part of routine maintenance. Others are said to be maintenance free, with the lubrication and seal expected to last for the duration of the ball joint's projected lifespan. When the seal is compromised and the lubrication leaks out or grit and grime work their way in, the conditions are set for ball joint wear because the lubrication serves to reduce the primary contributing factor to wear -- friction.

Wear

    Clicking is one of the earliest noises heard when wear begins to affect the performance of a ball joint. According to Popular Mechanics, the clicking noise is a subtle sound felt as much as heard via the steering wheel. As time goes by the click becomes louder, turning into a clunk, then a thunk particularly noticeable when driving over rough terrain.

Failure

    This is a ball joint problem that should be avoided if at all possible, as failure can be both dramatic and dangerous. When a ball joint fails completely, the wheel can come out of position to such a degree that the frame of the vehicle hits the ground. If this occurs at a high rate of speed, the wheel can detach completely. In order to avoid this type of ball joint failure, and its potential to cause traffic accidents and significant personal injury, be sure to heed the lesser symptoms of ball joint problems early on. Even if there are no obvious symptoms of impending ball joint failure, follow manufacturer's recommendations concerning ball joint maintenance and replacement schedules to ensure safety.

Problems With the Maxima IACV

The idle air control valve, or IACV, in the Nissan Maxima is responsible for regulating the amount of air that flows through the throttle body to maintain a constant idle speed. Maxima's powertrain control module controls the IACV electronically. Problems with the IACV will cause your car not to idle properly or even to stall out. The Maxima should idle at a speed of approximately 1,000 RPM when it is not in gear and 800 RPM when it is in gear.

Air Leaks

    If your Maxima's engine has developed an air leak somewhere in the manifold or throttle body, the computer may close off the airflow that is coming through the IACV in an attempt to hold in air and maintain the proper idle. Too much air will cause the vehicle to idle too fast, increasing the engine's RPM reading at an idle. This will result in the idle air bypass solenoid extending all the way out and restricting the airflow through the valve entirely, rendering the valve completely ineffective for maintaining proper idle speed.

Electrical Problems

    The idle air control solenoid can experience a short within the wiring or circuits that will cause your Maxima's check engine light to come on and cause the vehicle's computer to generate error codes. This may cause the IACV to stop working and the vehicle may idle poorly or even stall out when it is supposed to be idling.

Vacuum Leaks

    Vacuum leaks will affect the amount of airflow your Maxima's idle air control valve is receiving and can cause the vehicle to idle both too high and too low. Vacuum leaks are not actually a problem with the idle air control sensor itself, but with the connections to and from the control sensor through the throttle body and intake. Vacuum leaks are a common cause of idling problems, which are then typically blamed on a faulty IACV. It is important to check your Maxima for vacuum leaks before replacing the IACV on your motor.

How do I Troubleshoot the Sensors on a 1988 Toyota Pickup?

Troubleshooting the sensors on a 1988 Toyota pickup requires a computer and some knowledge about how the vehicle works. Keep in mind when diagnosing the problem that one thing always affects another thing. For example, if you get an oxygen sensor soft code, you should not assume that the oxygen sensor is bad. Check other parts that might affect it such as a bad plug wire or spark plugs. These problems could disrupt the amount of unburned fuel in the exhaust. That could cause the oxygen sensor to have bad readings, which in turn causes the computer to turn on the check engine light with an oxygen sensor code.

Instructions

    1

    Plug the code scanner into the data port, which is located under the dash just to the left of the steering wheel. Turn the car key to the "On" position.

    2

    Press the "Read" button on the scanner. Write down the codes as the scanner displays them. Match the codes to the code sheet that comes with the scanner. The code sheet converts the code to a meaningful diagnosis.

    3

    Check the plugs, wires and the rest of the ignition system if you have an oxygen sensor code and if the light never stays on. The light could go off when you first start the vehicle, then come back on or it could go off while driving.

    4

    Have a professional check the computer if the code scanner gives you too many codes that do not make sense. If you receive four or five codes, chances are you have a malfuntioning computer. Not that many sensors usually go bad at the same time. If you have codes that do not exist, you also could have a problem with the computer.

1995 Dodge RAM Transmission Troubleshooting

1995 Dodge RAM Transmission Troubleshooting

The 1995 Dodge RAM pickup truck is tough enough to withstand harsh weather, wet driving conditions and uneven terrain. After a while, though, its transmission may begin to show signs of wear. If your 1995 Dodge RAM is slipping when you shift gears or if it is leaking reddish fluid, you may need to troubleshoot its transmission. You can do this on your own without taking it to a mechanic, although you may need to consult a professional after diagnosing a problem. You will not need any tools to troubleshoot your RAM's transmission and it should only take an hour at most.

Instructions

    1

    Start your Dodge RAM and try to downshift the transmission while you push the gas pedal down. Pushing the gas usually drops the RAM into a lower gear to accommodate the greater amount of gas flooding into its combustion chamber. If your RAM does not downshift, the throttle cable will need to be adjusted by a mechanic.

    2

    Try to start your Dodge RAM in gears besides "park." If it starts, the neutral start switch is damaged. It will need to be serviced by professionals.

    3

    Inspect your RAM to see if it is leaking reddish fluid. Such a leak is due to a broken or weakened transmission seal. Consult a mechanic to fix this seal.

    4

    Note whether the transmission shifts sloppily or slips when shifting. This could be a result of low transmission fluid level. If the transmission fluid is at an acceptable level, the transmission itself may be at fault: the gear teeth could be corroded or the synchronizers could be damaged. The transmission will need to be inspected by a trained professional familiar with Dodge transmissions.

Kamis, 29 Juli 2010

What Makes the Water Not Flow Through the Heater Core on a 1993 Town Car?

If you've already deduced that you've lost flow through your Town Car's heater core, then you already know what the heater core is: a small radiator that works just like your main radiator but harnesses hot air instead of expelling it. Your car's heating system is a simple thing, but it can fail in a number of ways you might not expect.

Checking the Source of Flow Restriction

    Assuming the hoses aren't kinked, there are really only two places where your heating system can impede flow: at the valve or in the core itself. First, get your engine up to operating temperature; then turn the heater on to "Full" and the blower fan on to "Low." Locate the heater coolant valve near the firewall -- it's the only big, plastic thing poking up out of your heater tubes. Gently wrap one hand around the engine-side feed tube on the forward side of the valve and the other hand around the hose on the other side. If one is noticeably colder than the other, then the valve is your problem. If they're the same temperature, feel the core output hose. If it's noticeably cooler than the input, your clog is in the core itself.

Malfunctioning Valve

    The heater valve, a sort of "vacuum motor," gets its motive power from engine vacuum routed to it through the vacuum distribution channel. The seals and shafts inside these valves can and do fail, causing the valve to remain shut and impede coolant flow. The simple test here is to disconnect the two vacuum lines one at a time and feel for vacuum in the lines. If you've got a good vacuum and the valve remains shut, then the valve is bad and in need of replacement. Don't worry about the electrical connector on the valve; it's just a sensor that interrupts power to the blower motor until the engine warms up.

EATC Unit

    If your vacuum test revealed a lack of vacuum to the valve, then you likely have a problem with the electronic automatic temperature control unit. The EATC unit, located behind the radio, is essentially a computer that interprets your climate-control needs and signals the appropriate servos and valves. Before replacing the EATC, try the EATC cold boot procedure to recalibrate it. First, remove the radio to access the EATC unit. With the ignition key in the "Off" position, unplug the two electrical connectors from the unit. Wait one minute, reconnect the EATC, turn the ignition to the "On" position and press any button except for "Off." Recalibration takes about 30 seconds. Give this a shot before laying out those dollars for a new, very expensive EATC unit.

Core Clogging

    If you've determined that the valve works -- using the simple procedure for checking the source of flow restriction -- and that your fluid stoppage happens in the core itself, then it's likely you've got excessive calcium, lime and rust buildup in the core. These mineral buildups happen primarily as a result of not using pure distilled water or antifreeze in the cooling system. To flush the core, disconnect the core lines from the engine, drain the water out of both and tape them to the hood with duct tape so they're pointing upward. Fill both with concentrated calcium-lime-rust remover and allow it to sit for a couple hours. Finally, press a garden hose to the output line and turn it on full blast to back-flush all that junk out of the core.

Rabu, 28 Juli 2010

How to Diagnose a Bad Idler Arm

How to Diagnose a Bad Idler Arm

Vehicles with conventional steering use idler arms to connect the ends of the tie rod to the vehicle's front wheels. Over time the bearings in the arm's bushings become worn, causing slack in the connection. Generally the only symptom of a bad idler arm is for the steering system to develop "play," causing the vehicle to not respond to minor movements of the steering wheel. To diagnose a bad idler arm you only have to observe the connections as the wheels are turned.

Instructions

    1

    Park the vehicle on a flat, smooth surface. For safety, block the rear wheels and set the parking brake.

    2

    Start the vehicle and set the front wheels to point straight forward. Move to the front of the vehicle and take up a position where you have a clear view of the idler arm assembly. Ask your assistant to rock the steering wheel back and forth, a few inches at a time.

    3

    Observe the connection at the end of the idler arm, where the shaft is set into the bushing near the wheel. Use the flashlight if necessary. If the shaft of the idler arm moves in any direction, prior to the wheel beginning to turn, the bushing is bad and the idler arm needs to be replaced.

How to Reset an ECM on a Dodge Stealth

The Engine Control Module, or ECM, on a Dodge Stealth is the engine management indicator for the automobile. It is the car's brain box, holding all the information about the car, such as the mileage. It tells all the car's parts what they need to do. When the ECM senses a problem with your car, it triggers a check engine light on your dash. In most cases, a problem with the ECM requires reprogramming at a dealership, but you can reset the unit by yourself in a few simple steps.

Instructions

    1

    Open the hood of the car, and locate the battery.

    2

    Identify the positive and negative terminals. The positive terminal will have a "+" sign, while the negative will have a "-" sign.

    3

    Loosen and remove the negative battery terminal with your wrench, and wait at least 15 seconds.

    4

    Replace the battery terminal with your wrench, close the hood, and start the car.

Selasa, 27 Juli 2010

Problems with Ford IAC Valves

The idle air-control valve is designed to regulate the idle on your Ford car or truck. A malfunctioning idle air-control valve can cause too much or too little air to flow through your vehicle's intake and cause it to idle high, low or even stall out. Idle air-control valve problems are typically not serious in terms of affecting your vehicle's operation, but they can be a nuisance.

Electrical Problems

    Shorts in the idle air-control valve's electrical wiring and circuits have been known to cause the IACV to malfunction in Ford vehicles. Electrical problems with the IACV have the potential to cause the vehicle to idle poorly or not at all due to too little air coming through the valve. Typically, these kinds of issues will cause the vehicle to generate error codes and your check-engine-light on the dashboard may illuminate.

Excessive Use

    Vehicles that spend a significant of time idling -- such as police cars or vehicles that are regularly driven in stop-and-go rush-hour traffic -- are more inclined to suffer idle air-control valve failures. These vehicle's IACVs undergo an unusually high amount of use and the components will break down more quickly than usual.

Air Flow

    It is possible for your vehicle's engine to develop an air leak in its manifold or throttle body and get too much air flow coming through. In this instance, the power-train control module will tell the IACV to close off airflow in an effort to regulate the amount of air traveling through the engine and the speed of the idle.

    Idle speed increases with air flow.

How to Troubleshoot Car Noises

How to Troubleshoot Car Noises

Vehicles can confound their owners with a variety of noises that come from one end of the vehicle or the other. Some noises can be temporary or sporadic, coming and going during different times of operation. These intermittent noises can be the most difficult to diagnose. Other noises start gradually and get progressively worse, which can tip off the vehicle owner to some potentially serious problems. Knowing what noises mean and their location can prevent costly repairs down the road.

Instructions

    1

    Drive your vehicle in an alleyway that has high walls on both sides. The narrower the alley, the better. High walls in proximity to the vehicle amplify sounds, making them very easy to hear. Roll all the windows down and listen carefully for anything that sounds unusual. Listen for squeaks, knocking, clacking, clicking, "plapping," hissing, grinding or swishing noises. Record any peculiar noises in a notebook, noting the noise and the approximate or exact location where it comes from. Make several passes with the vehicle.

    2

    Apply the brakes slowly while driving in the alleyway. If you detect any swishing or metal-to-metal grinding noises while applying the brakes, this means that the disc pads or the rear drum shoes have worn down past their useful life.

    3

    Listen for any clicking sounds that come from any one of the wheels while driving in the alleyway. Loose hubcaps, especially ones with a spoke-wheel design, will make such noises. The suspect wheel can be eliminated by removing the hubcaps one at a time to narrow down the clicking wheel. This clicking noise should not be confused with worn hydraulic lifters or rocker arms which will originate from the engine and not the wheels.

    4

    Drive the vehicle over parking stops at a slow speed. Listen for any hard clunking noises that come from the vicinity of the front suspension. Such noises could indicate a broken shock mount, a worn upper or lower ball joint, or bad or broken control arm bushings that have bottomed out the frame. The noises will be jarring or harsh-sounding.

    5

    Park the vehicle with the engine off and the emergency brake set. Move to the front of the vehicle and raise the hood. With the full weight of your body, step on the bumper and push downward. Listen for any squeaking sounds. Such noises indicate that the control arm bushings have dried out, or that the coil springs have shifted and become unseated. Dry ball joints will produce a squeak. Sometimes an anti-sway bar or idler arm will squeak as a result of wear or a dry joint.

    6

    Listen to any noises coming from the radiator while the engine is running. A stuck thermostat will produce a knocking noise that comes from the top of the radiator. A noticeable vibration can also be felt but be sure to use a rag instead of a bare hand to feel it.

    7

    Drive down the street under normal conditions. Listen for any sound that simulates a whining noise that increases with intensity or decreases with the automatic shifting of the transmission. This whining noise usually indicates a low transmission fluid level or contaminated fluid. This noise might be very similar to a power steering pump, except that a power steering pump might screech or howl much louder.

    8

    Place an automotive stethoscope over the top of the engine while it idles. Any clicking or clacking sounds coming from the valve covers or the intake manifold usually point to a stuck or worn hydraulic lifter, or a solid lifter out of adjustment. Remember that the camshaft (valve train parts) move at half the speed of the crankshaft, so for every two engine rotations, the camshaft will rotate once.

    9

    Move the stethoscope down to the side of the engine block with the engine running. Any muffled clanking noise within denotes a piston connecting rod that has worn on its piston journal or the crankshaft journal. These internal, heavy engine knocks will point to the main bearings, the crankshaft or pistons. This noise will be constant and frequent every time the engine rotates.

    10

    Turn on the air conditioning and listen for any screeching noises coming from the engine compartment. Such a noise points to a loose serpentine belt or AC pulley belt slipping on the pulley.

    11

    Listen for any back-fire engine noise that produces a very loud popping sound during acceleration or braking. This indicates a timing problem associated with a bad timing chain tensioner, a loose timing chain or belt, or a chain or belt that has skipped time.

    12

    Raise the vehicle on jack stands and run the engine in gear, listening for any "growling" sounds coming from the driving wheels. Such noises usually denote a worn or dry wheel bearing.

Senin, 26 Juli 2010

How to Test a Starter With a Multimeter

How to Test a Starter With a Multimeter

Multimeters allow you to test the current, voltage and resistance of your automobile's electrical system. When you perform a test on your car's battery, you also need to test the other components of the charging system to determine whether the battery is failing.



Testing the resistance of the starter with a multimeter is a fundamental step in diagnosing vehicle charging system problems. A starter that shows high resistance will drain power from the battery faster than the alternator can recharge it.

Instructions

    1

    Align one car ramp with each front tire of your vehicle. Drive the vehicle onto the car ramps. Place the vehicle in park and set the emergency brake. Turn off the vehicle.

    2

    Set one wheel chock behind each rear tire of the vehicle.

    3

    Lie down on the floor creeper and slide yourself under the vehicle. Locate the starter, which should be on the side or front of the engine.

    Wipe the cable running to the starter with a rag. Inspect the cleaned cable for nicks in its protective sheathing, or a loose connection between the starter cable and the starter bolt. Tighten any loose connections with an adjustable wrench.

    4

    Connect the positive and negative leads of the inductive current clamp to the positive and negative ports on the body of the multimeter.

    5

    Hook the inductive current clamp over the power cable that runs to the starter. Turn on the multimeter, and set it to "Resistance."

    6

    Read the multimeter display as an assistant starts the engine. Compare the display reading with the starter manufacturer's specifications. If the resistance reading is too high, try replacing the cable. If the problem persists, the starter is likely to have internal problems, and may need replacement.

    7

    Shut the vehicle hood. Remove the chocks from behind the vehicle's rear wheels and drive it down from the ramps.

Troubleshooting a 1995 Nissan Maxima Security System

Troubleshooting a 1995 Nissan Maxima Security System

Nissan's Maxima security system is a combination security system and immobilizer. It works by protecting the doors and trunk lid while the system is armed. It doesn't use any kind of motion detection. Problems with the system can be related to arming, activations, and the immobilizer, including the security indicator light and keys. These kinds of problems can be corrected by following some troubleshooting steps.

Instructions

    1

    Confirm that the security indicator light comes on if the system doesn't arm. Turning the key slowly when arming can cause the system not to arm. Arm the system by turning the key to the "Lock" position, and closing and locking the doors. Watch the light; it should stay on for about 30 seconds while the system pre-arms. After about 30 seconds it should flash every 3 seconds. When the light flashes every 3 seconds you will know the system is armed properly. If the system doesn't arm, try it again, turning the key more slowly.

    2

    Shut the alarm off if the vehicle has been tampered with and the alarm is activated and then the alarm sounds again. The alarm won't be deactivated until you turn it off. Simply unlock the driver's door to turn the alarm off.

    3

    Keep automatic toll road devices, second registered keys and automatic payment devices away from the key that you use if you can't start the Maxima. Interference from these types of devices can cause your registered key not to work properly. Place the key on a separate key ring if the engine won't start regularly.

Engine Noise Sources

Engine Noise Sources

Your car is bound to make some noises from the hood that will confuse and scare you over its lifetime. These engine noises can be the result of minor problems such as a clogged fuel filter or something altogether more serious like a damaged rod. Regular vehicle maintenance is necessary to catch these problems early before serious engine damage occurs.

Valvetrain Noises

    According to automotive repair website AA1 Car, valvetrain problems in your car's engine can be characterized by several distinct noises. A clicking or tapping noise that increases in volume when you accelerate can be an indication of low oil pressure, damage to the upper valvetrain or a clogged oil pump/filter. A low oil pressure reading can be indicative of a serious engine issue that's keeping engine oil from reaching the upper portions of the valvetrain.

Engine or Spark Knock

    Engine or spark knock occurs when the mixture of air and fuel flowing into the engine becomes too rich or too lean or when engine spark plugs begin firing incorrectly. Sounds are characterized as either a loud bang when the engine attempts to accelerate or a pinging or knocking sound while the engine is idling. Excess carbon in the engine's combustion chambers and an overheated engine can also cause the banging or popping noises associated with engine knock.

Deep Engine Noises

    If your vehicle's engine begins emitting a deep engine noise like the sound of metal rods clanging together, a hammering noise or a deeply resonant bang. a significant engine problem may be occurring. This can be caused by worn rod bearings which if not properly maintained can eventually fail and cause your vehicle's engine to seize up. Once this happens the effects can cascade throughout your automobile's components causing belts to slip and parts to collide.

Problems in 1997 Ford Explorers

Problems in 1997 Ford Explorers

Beginning in 1990, the Ford Motor Company began producing the Explorer, a mid-sized sport utility vehicle. The Explorer was originally built as a replacement for the Ford Bronco II and helped define the SUV as one of the most popular types of vehicles on the road. The 1997 Ford Explorer has, however, been associated with several problems and issues.

Engine Problems

    There have been many problems reported with the engine in the 1997 Explorer. The engine may crank but will not start. There have also been reports that the chain tensioner can fail and that the crankshaft can break off. Some owners have experienced cylinders that do not fire, as well as flashing engine lights and failure of the rear cassette.

Transmission Problems

    Owners have reported that the Explorer will not shift gears into reverse or drive, or that the transfer case clutch will begin to spin. Other issues include strange noises and slipping torque converters. Another major issue with this model relates to its four-wheel-drive system. Loss of four-wheel-drive capability has been reported by some drivers.

Other Problems

    There are other known issues with the 1997 Ford Explorer. These problems are less common, and repair costs are relatively low. There have been problems with suspension and steering, as well as brakes. Also, failure of the heater case and blend door can cause the heating and air conditioning to not work. In addition, there have been reported problems with the starter failing and battery charging.

Minggu, 25 Juli 2010

Signs & Symptoms of a Faulty Vacuum Pump in a Cummins Diesel Engine

Signs & Symptoms of a Faulty Vacuum Pump in a Cummins Diesel Engine

The vacuum pump in a diesel engine is used primarily to provide enough suction to provide the power brakes. In some engines it also provides power and suction for the A/C and ventilation systems. The vacuum pump is running all the time the engine is running so they do fail sooner or later and give off some very distinctive signs.

The Brakes Get Harder

    A vacuum pump failure will cause the brakes to become much harder to push than usual. The vacuum pump provides the suction needed for the power brake booster to function correctly so if the vacuum pump fails, the power brake booster will stop working as well and the brake boost will be lost. The brakes will still work but they will feel hard. Brakes that are gradually getting harder to push can be a sign of a vacuum pump beginning to fail.

Lack Of Suction

    Remove the hose from the vacuum pump while the engine is running and place your finger over the hole you should feel a strong suction. If you feel little or no suction then you may need to replace the pump. If you feel the strong suction at the vacuum pump but still don't have any braking power then check elsewhere in the system for leaks.

Oil Leaks

    Open the hood and locate the vacuum pump. Look around it for any oil leaks as they may indicate a problem with the seal. You can also listen for any hisses or whistles that may indicate air coming out although they will be hard to hear with the engine running.

How to Detect Transmission Problems

How to Detect Transmission Problems

Detecting transmission problems early can prevent expensive repairs. The transmission is one of the most important component in a vehicle. When there are problems with a transmission, there are generally early warning signs. Some signs may indicate that there is a minor problem, while others may mean that your transmission needs extensive repairs. If minor problems are corrected promptly, you may prevent them from becoming a major issue. With these suggestions you will quickly be able to detect problems with your transmission.

Instructions

    1

    Listen for strange noises coming from under the hood of your vehicle. Noises such as clanking, grating, knocking or a buzzing sound may indicate that there is a problem with your transmission.

    2

    Determine if there is slippage during acceleration. The engine of the vehicle will speed up during acceleration, but the vehicle moves slowly.

    3

    Start the vehicle, place your foot on the brake pedal, then put the vehicle in the reverse position. Shift to the neutral (N) position and then to the (D) drive position. If you feel an abrupt jerk when you shift between gears or hear unusual noises, this could indicate that the transmission has a defect.

    4

    Check for transmission leaks under your vehicle. This is best done by checking the parking space you have used immediately after backing out of it. Transmission fluid has a dark red appearance. If you see a pool of dark-red fluid where the car had been parked, immediately check the transmission fluid level in the car and add more if necessary. Get the vehicle checked out as soon as possible to determine what is causing the leakage.

    5

    Determine if there is a strange smell coming from under the vehicle or under the hood. Rancid or burnt odors probably indicate transmission problems.

Probable Causes of a Power Steering Fluid Leak

Probable Causes of a Power Steering Fluid Leak

In 1927, General Motors began experimenting with hydraulic power steering in their vehicles, but the maker axed the program when it deemed the cost too high. Until 1951, drivers depended on large steering wheels to get enough leverage to turn the front wheels. Chrysler finally relieved customers of this daily workout by fitting the 1951 Imperial with Hydraguide power steering. When the fluid begins leaking from the system, it is important to find the cause of it to avoid damage to the system.

Case Halves

    When assembling power steering pumps, the manufacturer puts the pump together in two halves with a seal between the two. With age, or due to defect, the seal between the two pumps can crack, resulting in a leak. The only way to repair this is to split the two halves and install a new seal, or replace the pump altogether.

Reservoir

    Most power steering pumps have a reservoir that sets on top of the pump or in a remote area away from the pump. Manufacturers typically make this reservoir out of a hard plastic. This plastic endures a lot of heating and cooling from being near the engine. This heating and cooling can lead to the reservoir cracking, which results in a leak. Replacing the reservoir is the only way to fix this issue permanently.

Hydraulic Lines

    The power steering pump is constantly under pressure while the vehicle is running. Automobile manufacturers install hard lines to transfer this fluid from the pump to the steering rack or box to handle this pressure. Over time, or due to damage, these lines may begin leaking from either the tubing or the unions. If the tubing leaks, you must replace it, but repair the union using thread sealer.

Steering Rack or Steering Box

    Depending on the vehicle, the steering system has either a steering rack or steering box. The steering rack is a long cylinder connecting the front wheels. Hydraulic pressure moves an internal piston back and forth to move the front wheels. This rack has a seal on either end to keep the power steering fluid inside the rack. When this seal fails, the fluid will leak out. The only way to rectify this problem is to replace or rebuild the steering rack.

    Typically, only large trucks and older vehicles use a steering box. Hydraulic fluid turns a large gear inside the steering box and an output shaft transfers the movement of this gear to the steering linkage. This box has several gaskets -- the exact number depends on the type of vehicle -- and these gaskets can start to leak over time. Rebuild or replace the pump to rectify a leaking steering box.

Sabtu, 24 Juli 2010

How to Check the Maintenance Codes for a 2005 Acura

Your 2003 Acura uses a second-generation onboard diagnostic module called the OBDII. The OBDII constantly monitors your Acura for issues with your engine, brakes and fuel delivery, among other things. When the OBDII identifies a problem with the Acura, the check engine light comes on to notify you that there is a problem. In the past, you had to take the vehicle to a repair facility to have the maintenance code checked. Now you can do it in the comfort of your own garage with an OBDII code reader and the code book that goes with it.

Instructions

    1

    Plug the OBDII code reader into the OBDII port located under the dash panel on the driver's side of your Acura.

    2

    Turn the ignition key to the "auxiliary" position. This turns on the OBDII code reader and the vehicle's OBDII system.

    3

    Select "read trouble codes" on your OBDII reader. The reader displays a code that is specific to the issue that the system has identified.

    4

    Look up the code in your code book to determine the problem that the system has identified.

Signs & Symptoms of a Torque Converter Clutch Malfunction

The torque converter in your vehicle is essentially the piece of equipment that allows power from your engine to be transferred to your transmission and drive train. Problems with your torque converter can be serious and cause your vehicle not to run correctly or cause damage to important and expensive components of your drive train, such as your transmission. The torque converter clutch is designed to provide power by only turning in one direction. If the clutch breaks or stops working, your car can experience several different problems.

Loss of Power

    If the one-way clutch in the torque converter gets stuck in place and will not allow the converter to circulate the hydraulic fluids, it can cause a loss of power in your vehicle when it is traveling at higher rates of speed. This means that if your vehicle is traveling at 50 or 60 miles per hour and you go to pass someone, it may not have the power it should to pass or accelerate.

Overheating

    A malfunctioning torque converter clutch will not circulate fluid properly and can cause the engine and transmission to overheat. The engine will overheat due to the extra pressure it has to exert to power the vehicle. The transmission will overheat because the fluids are not circulating properly and are failing to keep it cool. The transmission may burn up if this occurs and have to be completely replaced.

Acceleration Problems

    The torque converter clutch is designed to be a one-way clutch. If it breaks and starts moving in both directions, your vehicle will have a difficult time building up the power it needs to accelerate. This means that the vehicle will accelerate very slowly or, in some extreme cases, it may not move at all.

Jumat, 23 Juli 2010

How to Troubleshoot the Heated Seats in a 2006 Chevy Silverado

How to Troubleshoot the Heated Seats in a 2006 Chevy Silverado

Chevrolet's Silverado trucks can be supplied with heated seats as part of an optional comfort package. Other seat options can include power operated seats; power lumbar; and memory seats, coupled with memory mirrors and pedals. Problems with the heated seats in a 2006 Chevy Silverado can be related to them not coming on, not staying on and the incorrect temperature. You can rectify these kinds of problems by following some troubleshooting.

Instructions

    1

    Press the correct control if the seat isn't heating properly. The seatback on its own, and the seat and seatback together can be controlled separately. The controls are located on the driver and passenger doors. Press the heated seatback switch, which is the control with the heat waves icon superimposed on a seatback icon, for seatback heating on its own. Press the other control---which has an icon of heat waves passing through both the seat back and the seat---to turn both seat and seatback heating on together.

    2

    Press the button multiple times if the temperature is uncomfortable. Each press toggles through the settings which can be "Off," "High," "Medium" and "Low." The lights show the level selected with one light for low, two for medium and so on.

    3

    Restart the engine and press the heated seat buttons again if the engine is turned off and the seats become cold. The seats will only heat while the ignition is on. They will be turned off if you turn the ignition off.

Can Bent Rims Cause Car Vibrations?

Can Bent Rims Cause Car Vibrations?

Bent rims are among several things that can cause vibrations in a car. They can also be difficult to detect. It's important to verify that the vibrations are caused by bent rims on the wheels rather than another problem.

Speed

    There may not always be vibration when the car is moving. It's common for bent rims to not cause vibration until the vehicle is moving at a higher speed. The automotive website AA1Car says vibration usually starts at a speed of 40 to 50 miles per hour.

Alignment

    Misaligned wheels can cause vibrations similar to the ones created by a bent rim. If the steering while vibrates along with the tires, the problem is likely with the vehicle's alignment.

Checking Yourself

    Money can be saved by diagnosing a bent rim at home. It's possible to spot it by lifting your vehicle off the ground with a jack and spinning the tire. If the wheel has an uneven spin, it's likely the rim is bent.

In a Shop

    Wheel repair shops have machines that test the balance of the tires. Bent rims usually don't need to be replaced because most shops can repair them.

Kamis, 22 Juli 2010

Troubleshooting a 1998 Chrysler Concorde Climate Control System

Troubleshooting a 1998 Chrysler Concorde Climate Control System

Chrysler's Concorde automobiles were supplied with a manual air conditioning and heater system. Some vehicles included an automatic temperature control, known as an ATC. The manual system is regulated by a knob with gradations for cold to hot. The ATC system keeps a steady temperature regulated by sensors. Problems with the systems can include fogging, poor heat results or poor air throughput.

Instructions

    1

    Press the "Defrost" button on the dash if the rear window fogs up. Then select either the "Defrost" setting on the climate controllers, or the "Mix" setting. This will keep the front window clear. Increase the blower speed if the side windows fog. Non-adjustable side window demisters are located on the instrument panel and blow air at the forward part of the window --- where the mirrors are located.

    2

    Clear any packages, kid's toys, or other items from the foot wells in the rear if the rear doesn't benefit from the climate control system in the same way the front does. On 50/50 front bench seats air is routed under the seats. On a bucket-seat version of the Concorde, the air is passed through upper and lower outlets on the center console. Adjust these for maximum benefit.

    3

    Remove anything that could be blocking the ATC sensors if the ATC doesn't regulate temperature properly. The sunlight sensor is located in the center of the instrument panel and maps, gloves and other items will cause incorrect readings. The cabin temperature sensor is behind the ATC panel in the dash. Avoid sticking devices like cell phone holders there. Remove anything and try the system again.

Signs & Symptoms of a Blocked Air Filter on a Car

Signs & Symptoms of a Blocked Air Filter on a Car

In an automotive engine, the air filter acts as a barrier between the intake system and the ambient air required for fuel combustion. A congested or blocked filter requires the engine to work much harder to draw in air, leading to numerous performance issues. The signs and symptoms of a blocked air filter make the problem relatively easy to diagnose. Furthermore, you can quickly inspect and replace the air filter by following the service procedure recommended in your car owner's manual.

Diminished Power and Acceleration

    To generate power, the engine requires an adequate amount of air to mix with fuel for combustion. A blocked air filter restricts the airflow into the engine, thus reducing the power output. This is especially evident under heavy acceleration, as the engine requires an increasing amount of airflow to feed the cylinders as its rpm rises. With a blocked air filter, the engine may feel hesitant under acceleration, especially in the upper rpm range. In extreme cases, the engine may be unable to accelerate beyond a certain speed or rpm due to inadequate airflow.

Sputtering and Stalling

    A severely clogged air filter can cause the engine to sputter or even stall. When the engine is unable to draw in an adequate amount of air, it can experience an overly rich air-to-fuel ratio. This leads to an inefficient combustion process, with excess fuel remaining in the cylinders after each piston cycle. With an extremely rich air-to-fuel ratio, the engine may hesitate and sputter when accelerating and may even stall when you lift off the throttle. In less extreme cases, the abundance of leftover fuel in the cylinders will create a strong gasoline smell from your car's exhaust system when the engine is running.

Fuel Economy

    Older vehicles with carbureted engines will have a significant drop in fuel economy when the air filter is blocked. Since a blocked filter restricts the airflow into the intake, the engine is not able to achieve a proper air-to-fuel ratio, and thus the efficiency of the internal combustion process is severely reduced. However, most modern vehicles with fuel-injected engines will have a much less dramatic drop in fuel economy. In addition to air-to-fuel ratio issues, a clogged filter slightly reduces fuel economy by requiring the engine to work harder to draw air through the filter.

Inspection and Replacement

    Refer to your vehicle owner's manual to find out the suggested maintenance schedule and replacement procedure for the air filter. Regardless of the mileage interval suggested in the owner's manual, you should inspect the intake system immediately if your vehicle displays the symptoms of a blocked filter. On most cars, the air filter is inside a black plastic air chamber, accessible in the engine bay. Remove any metal clips and/or screws securing the plastic lid, then lift it free to access the filter. If the filter is clogged with dirt and debris, replace it with a new unit before reinstalling the air chamber lid.

Rabu, 21 Juli 2010

How Do You Find Out If a Fuel Pump Is Bad?

How Do You Find Out If a Fuel Pump Is Bad?

Now that you've suspected the fuel pump is bad, you're only steps away from determining the severity of the problem. Symptoms can include your car failing to start or accelerating poorly. How you troubleshoot the problem depends on what type of fuel pump is in your car. Whatever the case, there are other parts to diagnose before investigating the fuel pump. Even if the pump is bad, a basic replacement is all it will take to get your car in better shape.

Instructions

    1

    Determine pump type. Your troubleshooting the fuel pump depends on whether your car has a carburetor- or fuel-injected (EFI) system. If the EFI, you'll most likely need to perform an electrical test with a multimeter. Check your vehicle's manual to determine what system is in your vehicle.

    2

    Compare symptoms. A poorly-functioning fuel pump may cause hard starting, poor idle quality, hesitation or stumbling when accelerating, and a loss of power at higher speeds. And if your car fails to start completely, then your fuel pump may be the culprit.

    3

    Consider past maintenance. Check whether you or a previous owner had ever changed the fuel filter. If it was never changed, and you're experiencing poor engine performance rather than a failure to start, start by changing the filter. Check your owner's manual or a corresponding repair manual for the procedure.

    4

    Check basic functions. If your car has an electric fuel pump, you may have a simple electrical problem and not a pump problem. Check for a blown fuse in the fuse box, as well as for insufficient battery voltage. Also, check the wiring to and from the pump to see if there's a loose wire.

    5

    Do a pressure test. Tap a pressure gauge into the fuel supply line with the engine off, but the fuel pump energized (electrical system on). Another test -- a fuel flow test -- doesn't require a pressure gauge. In this test, disconnect the fuel line while the engine is off. Energize the pump and allow the fuel to be pumped into a container. Measure the flow and compare with the proper specs.

    6

    Perform an electrical test and measure amperage. Connect one multimeter lead to the positive battery post and the other lead to the hot wire of the fuel pump. Check a service manual for exact procedure, and compare the measured amperage with what's normal for your fuel system. If the reading's too high, your pump is bad.

How to Make a Magneto Tester

Using tightly wrapped wiring around a rotating magnet, a magneto uses movement, usually provided by an engine, to create an electric current. This current is often used to provide electricity to spark plugs in gasoline engines, and because of the prevalence of gas-fueled engines, magnetos are common in everything from automobiles to lawn mowers. The wire winding makes magnetos difficult to visually diagnose when engines have spark-plug issues, so test a magneto to determine if it still creates current.

Instructions

    1

    Determine the amount of current the magneto to be tested should produce using your operators manual or another resource. Damaged magnetos may be able to spark, though not produce enough current necessary to power the plugs. Determine if the magnetos spark is adequate to perform in the engine.

    2

    Determine the amperage of the current the magneto produces when operating properly by research in an operators manual or repair guide. Apply the amperage figure and voltage using Ohms law to determine the resistance of the spark plug assembly, using the formula R = voltage/amperage.

    3

    Purchase a resistor with an impedance value as close to the value of R determined in Step 3 without exceeding the value. If necessary, purchase multiple resistors to approximate the total load of the spark plug assembly.

    4

    Connect one of the resistors terminals to a LED, using insulated copper wire and wire stripper. Attach a separate piece of insulated copper wire to the other contact on the LED, and a third piece of wire from the resistors open terminal, creating an open circuit that runs as wire, resistor, wire, LED, wire.

    5

    Strip the final inch of insulation off each unattached end of wire. Insert wire into both ends of a magentos terminal, and rotate the magneto by grasping its central arm and turning. If the LED lights while the magneto spins, that terminal operates properly and produces enough current to meet the engines needs. If the LED fails to light, the magneto needs to be repaired or replaced.

What Can Make a Car Die When You Come to a Stop?

What Can Make a Car Die When You Come to a Stop?

The vast majority of reasons a car stalls at stops are related to engine performance. Factory dealer technicians may refer to driveability issues, while mechanics in an aftermarket shop might cite tuneup problems. Whatever terms are used, the condition could have serious consequences. The loss of power assistance for steering and braking can impede control of the car. Stops may be incomplete due to lack of braking power assistance, and the crippled car could enter cross traffic. Losing control of a car in a busy parking lot or at a railroad crossing can be hazardous, to say the least. The root cause should be properly addressed, even if unorthodox adjustments or rigged repairs seem to relieve the stalling symptom.

Electric Avenues

    The charging system is the source of electricity for all car functions.
    The charging system is the source of electricity for all car functions.

    As any fledgling mechanic soon learns, good engine performance begins with the car's battery. The battery stores electrical energy for the charging system. If the system is compromised, it may become incapable of powering vital engine components that deliver and ignite the fuel. An alternator is driven by a nylon-reinforced rubber belt that spins along with the crankshaft, and when the engine slows at stops, so does the alternator. At idle speeds, any shortcomings in the charging system can halt electrical energy generation or storage, and it's lights out for engine functions. A weak battery can overtax and ruin a good alternator, and a underachieving alternator can do the same to the battery. Comprehensive tests of a charging system should include alternator belt tension checks and cleaning battery cable connections, if needed. The starter motor may also at fault if it draws too deeply from battery reserves.

Fuel Starvation

    Sufficient fuel must reach the combustion chamber of the engine for it to run under all conditions. Even slight interruptions can shut down an engine at idle. Such interruptions can escape notice when under way, as momentum keeps the engine turning during a momentary lapse at cruising speeds. Carbureted cars might starve for fuel because of a weak mechanical pump, or a low level in the float bowl. The low level may be the result of incorrect float settings or a clogged fuel filter. The fuel nozzles of injected engines can be fouled by deposits that interfere with proper delivery at idle speeds. In any case, incomplete fuel disbursement can cause stalls when the car stops. Another cause may be an underachieving fuel pump that is not delivering the prescribed amount of fuel pressure. A competent technician would recognize and repair the source of the starvation.

Too Much of a Good Thing

    An engine that receives more fuel than it can use is said to be running rich. Airflow through an engine at speed may help alleviate symptoms while cruising, but at lower rpm, the rich mixture fouls spark plugs, engine sensors and exhaust system passages. The longer the engine is allowed to run rich, the worse the fouling becomes. Spark plugs may recuperate once the mixture is corrected, but sensors and exhaust components may need to be replaced to correct the fault, or to prevent corruption of the actual remedy.

Throttles

    Precise amounts of air are metered through an engine to provide a smooth and steady idle speed. The idle speed screw of a carburetor adjusts the throttle plate openings for flow, while a motorized air control valve is charged with this task on fuel injected engines. Neither method is successful if the air filter is packed with grime or obstructed by debris, like leaves that may be drawn into the filter housing. Idle controls can fail without warning, allowing the car to run well until the accelerator is released. Stalling may also occur if the engine is not held in place firmly. Broken or weak motor mounts can permit the engine to edge forward slightly when bringing the car to a stop. Throttle cables or linkages bind and distort the throttle shafts and plates, cutting off needed air. The extended service intervals for modern cars may be a dubious service at times --years can go by before a car is seen by a trained and certified technician.

Problems With the 1999 Mercedes M430

Problems With the 1999 Mercedes M430

Mercedes-Benz is well-known as a maker of high-performance luxury cars. The 1999 Mercedes Benz M430 (ML430), model is a sport/utility vehicle (SUV) with a 24-valve single-overhead V8 cam engine, a front-engine four-wheel drive and a 19-gallon fuel capacity. The introduction of the ML430 into the Mercedes-Benz auto lineup 12 years ago established its reputation as "the premier luxury car" with the capability of a truck's performance. Despite the ML430's attributed value, the National Highway Traffic and Safety Administration (NHTSA) issued two safety recalls for nearly 300,000 vehicles.

Faulty Seatbelt Assembly

    The ML430 seatbelt latch was incorrectly assembled, which could cause sudden detachment of the seatbelt from the seatbelt buckle. Serious personal injury or death could occur during an accident in the event of this malfunction.

Dimmed Headlights

    The ML430 headlight installation failed to comply with federal motor vehicle safety standards. This may cause gradual decreased visibility and subsequent vehicle accident.

Power Steering Issues

    Used Cars Auto Sales listed this recall on the ML430 regarding the loss of power steering fluid resulting from an improper connection between the power steering hose to the power steering cooler. The attrition of power steering fluid lessens the power steering performance over time and can lead to a spontaneous car crash.

Why Does a Car Stall While Idling?

Why Does a Car Stall While Idling?

Car engines rely on a delicate balance between multiple components to run smoothly while idling, according to the 2 Car Pros website. Car owners may have to check the electrical system, the throttle assembly and the exhaust system for problems.

Normal Idling

    During normal idling, the cars onboard computer alters the air-to-fuel mixture to keep the engine running at low speed. An idle air control motor enables this process by regulating air passage through the throttle. Stalling at idle indicates a fault in one of these systems.

Causes

    If the electronic sensor system develops a problem, the computer could direct the wrong mix of air and fuel to the engine, leading to stalling while idling. A leaky vacuum hose, a dirty throttle body, a faulty exhaust valve or bad idle motor can also make a car stall at idle.

Troubleshooting

    To troubleshoot an idling problem, the 2 Car Pros website recommends starting with a check of the electronics, including trouble codes and voltages. Troubleshooters can also try listening for whistling noises, indicating a hose problem. Deeper troubleshooting may require removal and inspection of the idle air control motor or exhaust valve.

Headlights and Moisture Problems

Headlights and Moisture Problems

Moisture from rain or snow can cause headlights in vehicles to become cloudy or dirty. This can make headlights appear dim, yellow and/or frosty, causing them to function poorly and threaten a driver's safety.

Identification

    If you are driving at night and notice that your headlights appear to have lost some brilliance, you could have fogged or dirty headlights. To identify condensation in headlights, look at the plastic cover. If the headlight cover looks white, or the lens is fogged or discolored, moisture has likely crept inside. Moisture can get in through a crack or an edge that has lost some sealant.

Prevention

    Prevent moisture before it happens. Applying dielectric grease to the headlight socket before the light's installation prevents corrosion and seals out moisture. However, if you are not experienced with auto maintenance, have this done professionally.

    Headlight sealers can sometimes loosen due to hot conditions. To ensure this doesn't happen, apply a an extra premium grade sillicone sealant along the frame of the headlight shell when the car is new. Then smooth out the sealant with your finger.

Solutions

    Fix any moisture probelms to ensure visibility while driving at night. You can remove the headlight cover and attempt to wipe or scrape off the film of moisture. Then use an auto sealant to recover the headlight cover. Professionals are well-trained in this process, so when in doubt, use their services.

    Another option is to drill small vent holes on the top of the headlight cover during dry weather. Leave the car in the sun for a few hours to evaporate moisture. Then seal the holes with sillicone glue or tape.

Selasa, 20 Juli 2010

Auto Diagnostic Scan Tools

Auto Diagnostic Scan Tools

The "Check Engine" warning light on the dashboard of your car or truck appears anytime the electronic control module reports a problem in any of the vehicle's mechanical components. The "Check Engine" light is a signal to car owners that there is a problem with their vehicle that needs to be repaired.

Diagnostic Scan Tools

    Diagnostic scan tools have been in use for more than twenty years. Before 1996, all the different car manufacturers had their own diagnostic equipment and codes that were unique to their vehicles. This meant that only a Ford code reader could read Ford error codes. Code readers were prohibitively expensive for most vehicle owners and many repair shops, sometimes costing upwards of $2,000, and would only work on some cars. In 1996, the EPA decided that all cars and trucks sold in the United States had to share the same general computer interface, an,d in turn, all use the same computer diagnostic equipment. Hence, the current code system was born.

OBD II

    The second version of the On-Board Diagnostic system, called OBD II, is found in all cars and trucks manufactured in the United States since 1996. All of the electronic systems and sensors in your car or truck are run by the vehicle's powertrain control module (PCM), which is the vehicle's computer. When the PCM senses a problem with any of the hundreds of sensors and components it monitors or controls, it triggers the "Check Engine" light, otherwise known as the malfunction indicator light. The computer also logs an error code in its memory that corresponds directly with the malfunction. Because of the OBD II standard system, the codes can then be scanned and retrieved with any OBD II diagnostic scanner.

Scanning for Codes

    OBD II code readers are relatively inexpensive and widely available now. The cheapest models sell for between $20 and $40 dollars at most auto parts stores. Auto parts stores also typically offer free diagnostic scanning services if you drive the car to their location. The scanner will be hooked up to the PCM and the car will be scanned for error codes. One or more codes may be found by the code reader.

Reading Error Codes

    Error codes come in both generic and manufacturer-specific formats. The easiest way to determine what error code is connected to what part is to look it up in commonly available lists of codes. These lists of error code meanings are available at your local parts store and on the Internet, and basic code meanings will come with your code reader if you purchase one.

Symptoms of a Clogged Cabin Filter

Symptoms of a Clogged Cabin Filter

A vehicle's cabin filter is part of the air-conditioning system, leading to it sometimes being referred to as an air-conditioning filter. These filters are often made of paper or cotton material. They remove pollutants from the air before they enters a vehicle's cabin. A clogged filter can negatively affect the air-conditioning system's efficiency.

Reduced Airflow

    A clogged cabin filter can reduce the volume of air that can pass through. This means air passing through the air-conditioning system slows down, thus reducing the flow of air into the cabin of the car. Vehicle owners may have to turn up the fan settings on their air conditioner to compensate for the reduced airflow, putting a strain on the air-conditioning system as it tries to blow more air into the cabin.

Reduced Horsepower

    A vehicle's engine provides power for the air-conditioning system's components. When the cabin filter is clogged, the system has to work harder and requires more power from the engine to do so. This reduces power to other components such as the drive train and alternator. As more power is diverted into meeting the needs of the air-conditioning system, overall horsepower and performance can suffer.

Increased Cabin Temperature

    An overworked air-conditioning system with reduced airflow is less able to keep the a consistent cabin air temperature. The air temperature increase caused by a clogged cabin filter may be gradual or significant, depending on how the filter is clogged, as well as other factors such as the outside temperature and amount of sunlight heating the air as it passes through the car's windows. When the air temperature starts to rise, the air conditioner simply can't produce enough cool air to reduce the temperature.

Increased Air Pollutants

    More dust, pollen and other airborne pollutants make their way into a vehicle's cabin when the air filter is clogged. This is a result of the air conditioning system pulling air through and around the filter.

My 1964 Ford Galaxie Won't Downshift to First When Stopped

The 1964 Ford Galaxie was made available with an optional heavy-duty three-speed automatic transmission. The transmission consists primarily of a gear train and a torque converter. Like all automatic transmissions, the Galaxie's transmission relied on pressurized fluid to change gears. The fluid's pressure depends in part on the speed of the engine. If the transmission fails to downshift to first gear, chances are good that the engine is idling too quickly or its vacuum line or valve body is damaged. Fortunately, checking each possibility is a fairly straightforward process.

Instructions

    1

    Lower the engine's idle speed if the engine idles at more than 600 revolutions per minute as indicated by the car's tachometer. A single screw is located on the driver's side of the carburetor. Rotate the screw in a counterclockwise direction with a screwdriver to lower the speed.

    2

    Raise the car with a jack and lower it onto jack stands.

    3

    Inspect the entire length of the rubber vacuum line that protrudes from the vacuum modulator for cracks or sharp bends. The modulator is located at the back of the transmission and is circular in shape.

    4

    Remove the bolts that secure the transmission's pan to the bottom of the transmission with a wrench, then remove the pan to access the valve body.

    5

    Remove the bolts that secure the valve body to the interior of the transmission with a wrench, then lower the valve body off the transmission. Do not tilt the valve body.

    6

    Inspect the passageways on the top of the valve body and the linkage on the side of the valve body for damage. Replace the valve body if the existing one is damaged.

Senin, 19 Juli 2010

Will My Brake Booster Cause My Car to Misfire?

Will My Brake Booster Cause My Car to Misfire?

If your car is having trouble accelerating or feels sluggish, you may have a misfiring problem. While this can be caused by the brake booster, that's not always the case. Make sure you know what causes a misfire, and under what conditions the brake booster can cause one.

Misfiring Definition

    A misfire is when the fuel in a cylinder fails to explode for some reason. It can cause your car to stall or accelerate slower. You may be able to feel the misfire through the pedal when accelerating or hardly touching the pedal at high speeds. It feels like a slight jolt.

Brake Booster Causes

    The brake booster can cause a misfire, but this type of misfire only happens randomly. It might misfire today, but not tomorrow. According to AA1 Car, this is because a leak in the brake booster decreases the vacuum power and upsets the air/fuel mixture in your engine.

Other "Random" Causes

    The brake booster isn't the only component that can cause random misfiring. For example, the fuel injectors may be dirty from fuel buildup. This keeps the injectors from inserting fuel into the cylinder correctly. Also, a weak fuel pump or plug in the fuel filter can also cause random misfiring.

Some "Normal" Causes

    A misfire is much more likely to be caused by worn out spark plugs, bad spark plug wires or a run-down distributor cap. All of these keep the correct amount of electricity from lighting the air/fuel mix in the cylinder. However, this is not a complete list of what can cause a "normal" misfire.

My K2500 Will Not Shift Out of Second

My K2500 Will Not Shift Out of Second

GMC has published technical service bulletins (TSBs) on its K2500 truck and Suburban concerning transmission problems experienced by some owners. A TSB is a report sent from the manufacturer to technicians concerning common problems occurring with a vehicle. Some of the TSBs on the K2500 report that the trucks become stuck in second gear or other gears for various reasons.

Gear Shift Cable

    One part that may cause the transmission on the K2500 to stick in second gear is the gearshift cable, which attaches the gearshift inside the truck to the transmission linkage. The cable may come loose or break, causing the transmission to become stuck in the last gear the linkage was in before the cable broke. Damage to the cable can result from corrosion developing on the cable, which can make it weak and eventually cause it to stretch or break. One TSB published by GMC covers the harsh shifting that develops before the cable breaks.

Valve Body

    The valve body on an automatic transmission controls the flow of hydraulic fluid and directs the fluid to the appropriate clutch pack, which allows the transmission to shift to the appropriate gear. Another TSB issued by GMC addresses a new valve body that must be installed into the K2500 when problems occur with the old valve body. Once the old valve body fails, it blocks the flow of fluid into the clutch pack. The gears will become stuck, and the K2500 will not be able to shift into another gear or out of the last gear used.

Torque Converter

    The torque converter in an automatic transmission takes the place of the clutch in a manual transmission. The K2500 has lockup clutch that locks the turbine into place when the truck reaches third or fourth gear or 45 to 50 miles per hour. A bolt on the lockup clutch may cause the K2500 to become stuck in second gear and not allow the turbine to lock into place before reaching third gear. According to the TSB, the new bolt must be installed on the torque converter to correct this problem.

Linkage

    A common cause for the transmission on the K2500, or any other vehicle, to become stuck in second gear is a failure in the transmission linkage, which allows the transmission to shift the gears when the power train reaches the appropriate speeds. The linkage can jam, break or become loose, causing the transmission to stick in one gear. GMC has not published a TSB for this linkage problem as of August 2011, but one TSB does concern the harsh shifting that begins to occur when the shift cable becomes damaged, which can create problems with the linkage.

My Car Won't Start, But Makes a One-Time Clicking Noise

My Car Won't Start, But Makes a One-Time Clicking Noise

That dreaded clicking noise is one that can indicate a few different problems with your car. If your car won't start, you could be dealing with a dead battery, a bad starter, no fuel, or even an electronic problem. Diagnosing the issue is just a matter of finding out what is NOT the problem though the process of elimination.

Instructions

How to Diagnose Why Your Car Won't Start

    1

    Check the fuel. Don't rely on your gauge, and if in doubt add some fuel just to make sure there is enough to start the car. Try to start the car and if it still doesn't start you know that fuel isn't the problem.

    Make sure your car is in Park and the emergency brake is set.

    2

    Look closely at your dash board when you attempt to start the car. If your lighted panels don't come on or are very dim then it is likely that you are dealing with a dead battery. Either use a battery tester or simply hook the battery up to a charger or use jumper cables to hook up to another car battery in order to charge the battery enough to start the car. After you charge the battery if your car still won't start you may be dealing with a bad starter.

    3

    Call a mechanic to find out if there are any other possibilities before you purchase and replace the starter.

How to Disable the 1994 Toyota Camry Alarm System

How to Disable the 1994 Toyota Camry Alarm System

The 1994 Camry is an automobile manufactured by Toyota Motors. It came in both a two-door coupe version as well as a sedan. The Camry came equipped with a stock alarm system. Disabling the system temporarily for maintenance or repairs is a simple process that can be done quickly.

Instructions

    1

    Sit in the driver's seat of the Camry.

    2

    Look underneath the dash until you locate a small black toggle switch. It will be the only one present on the lower left side. This is the "valet" or "kill switch" for the alarm system.

    3

    Press and hold the toggle switch.

    4

    Turn the key in the ignition while holding the toggle switch.

    5

    Wait until the alarm system makes a single audible notification.

Sabtu, 17 Juli 2010

How to Troubleshoot a 2002 Ford Escape With Starting Problems

How to Troubleshoot a 2002 Ford Escape With Starting Problems

If your 2002 Ford Escape begins to have problems starting, you could save money by troubleshooting the problem yourself instead of paying a mechanic. Once you have diagnosed the problem, you can determine whether the cause is something that you can fix yourself, or if you will need to have it repaired by a qualified automotive technician. There are several common starting problems that you can check for before calling a mechanic.

Instructions

    1

    Examine the car's fuse box for blown fuses that are directly related to the ignition and starter. Refer to the diagram on the fuse box for the location of each fuse and replace if necessary.

    2

    Look for heavy corrosion on the battery terminals and loose battery cable connections. Corrosion should be cleaned with a wire brush on both the battery terminals and the cable connectors. Use a wrench to secure the cables tightly to the terminals.

    3

    Turn the ignition to the "On" position. Look for any warning lights on the dashboard that would indicate a problem, such as low fuel or oil lights.

    4

    Turn the headlights on. If the headlights or other exterior or interior lights are unusually dim, this could indicate that the battery has insufficient charge to start the car.

    5

    Crank the engine and listen for unusual sounds. Rapid clicking could indicate a bad starter. Any loud knocks, squeals or grinding sounds could indicate a larger problem, and should be diagnosed and repaired by a qualified technician.

What Are the Causes of Vibration on Trucks?

What Are the Causes of Vibration on Trucks?

While it is not uncommon for older model vehicles to vibrate in various ways while driving, noticeable vibrations in newer model vehicles tend to be a sign of a larger problem. Vibrations in your truck can be difficult to diagnose because there are a variety of things that can cause them to occur, including outside factors, such as rough roads. However, once you are certain it is your truck vibrating and that the vibration is more severe than the slight vibrations often caused by a running engine, look for several common problems.

Tires

    A variety of tire problems can cause a vehicle to vibrate. Tires with unevenly worn tread are one of the most common culprits of a vibration. The vibration is caused by the varying levels of tread coming in contact with the road at the same time, creating an uneven ride. Alignment problems or radial tires where the steel belt inside the tire is separating or otherwise failing also can cause a noticeable vibration. Out of balance tires also can cause a vibration.

Brakes

    Problems with your braking system can cause your truck to vibrate while stopping. Warped brake rotors are the most common cause of braking vibrations. In addition to a vibration, warped rotors may cause your calipers not to release completely and lead to uneven brake pad wear that will cause your brake pads to need to be replaced sooner than they should.

Suspension Problems

    Problems in your vehicle's suspension can cause the truck to vibrate. Broken or weak shocks, tie rods, wheel bearings and other components will make your truck's weight distribute unevenly and cause a vibration. Vibration problems will commonly be caused by the suspension in your truck's front end rather than the rear.

Kamis, 15 Juli 2010

Front Wheel Bearing Diagnosis

The front wheel bearings in your car or light truck allow the wheels to roll smoothly and support the weight of the vehicle. The most common symptom of a damaged or faulty wheel bearing is a noise that increases in pitch and volume as the vehicle's speed increases, and may also change as the vehicle is turning corners. Diagnosing noise and problems caused by front wheel bearing damage or failure takes just a few minutes using basic tools that most home mechanics already have at their disposal.

Instructions

    1

    Place wheel chocks behind the rear wheels and apply the parking brake. Slide the floor jack under the frame or lifting point of one front side of the vehicle. As a rule, cars that do not have a full frame (most front-wheel-drive cars fall into this category) have a reinforced area -- located a few inches behind the wheel on the lower edge of the body -- that is designed as a lifting point. Refer to your owner's manual for the specific location of the lifting point for your vehicle.

    2

    Lift the vehicle until the front wheel is off the ground, and place a jack stand under the frame (on trucks and older rear-wheel-drive cars) or front sub-frame (on front-wheel-drive and unibody cars) and lower the vehicle onto the stand.

    3

    Check the tires for uneven or choppy tread wear that may cause road noise similar to a bad wheel bearing. If uneven tread wear is present, rotate the tires according to the instructions in the owner's manual, and perform a test drive to verify the tires are not making the noise. If tread wear is not an issue, continue on to the next step in the procedure.

    4

    Grasp the tire firmly at the top and bottom of the tread. Attempt to move the wheel in and out from the top and bottom. Replace the bearing if there is any perceptible movement while attempting to move the wheel with reasonable hand force.

How to Troubleshoot a 1988 Oldsmobile

How to Troubleshoot a 1988 Oldsmobile

Oldsmobile was a brand of car that was produced for more than 100 years by General Motors. Founded by Ransom E. Olds in 1897, cars carried the Oldsmobile name until GM phased it out in 2004. During the 1980s, nine different cars carried the Oldsmobile nameplate. Many of these cars had similar versions in GM's other brands including Chevrolet, Buick and Pontiac. When your 1988 Oldsmobile is not performing properly, there are few things you can do to troubleshoot the car and get it running again.

Instructions

    1

    When driving, observe whether the car responds promptly or if it hesitates before accelerating. Hesitation can be an indication that the fuel filter should be replaced. Replacing the fuel filter should restore the engine's performance. If not, the car may need to be put on a mechanic's scope to determine if any of the electrical engine controls should be adjusted.

    2

    Observe how your 1988 Oldsmobile starts on cold mornings. Models with electrical options such as windows, door locks, air conditioning and other features that require a lot of power were manufactured with a powerful battery. On very cold days, these batteries may have difficulty starting the Oldsmobile engine. Remove the battery cables and clean the battery posts with a wire brush. Removing any corrosion from the battery posts will ensure all of the battery power is transferred through the cables to the start motor. Reconnect the battery cables and try to start the car again.

    3

    Turn off the engine and open the hood if the car is running rough. Remove the spark plug wires and spark plugs using a spark plug wrench. Replace the old spark plugs with new ones and reconnect the spark plug wires. Start the 1988 Oldsmobile again and observe the difference in the way the engine runs. It should now run smoothly and start up easily.

How to Troubleshoot a 2005 GMC Envoy

How to Troubleshoot a 2005 GMC Envoy

The GMC Envoy is a midsize to full-size SUV manufactured by General Motors. It ceased production following the 2009 model year. Common problems with the 2005 Envoy center around the fuel system and rear suspension. These are the first places to check when troubleshooting any potential issues the vehicle may have.

Instructions

    1

    Examine your fuel gauge on the Envoy's dash. If the gauge always reads low fuel or empty, regardless of the actual contents of the tank, then the fuel pump module has gone faulty and will need to be replaced. This repair should be performed by a qualified mechanic, particularly if the vehicle is still under extended warranty.

    2

    Ensure that the gas cap is tightly secure. A poorly secured or worn-down gas cap can be the reason that the check engine light comes on.

    3

    Examine the vehicle's suspension, looking for any lowering in the rear components. This can be a sign that the rear air springs have failed, and will need to be replaced.

Selasa, 13 Juli 2010

How to Troubleshoot a 1988 Acura Legend Transmission

How to Troubleshoot a 1988 Acura Legend Transmission

Transmission problems occur in all types of vehicles, but there various ways you can troubleshoot all of them before they become an expensive problem. Identifying these problems from the onset may prevent costly repairs for your 1988 Acura Legend's transmission.

Instructions

    1

    Pay attention to the ground underneath your car. Reddish fluid, or transmission fluid, leaks may be an indication that the vehicle's transmission is suffering. If there are leaks, search the vehicle for the source of the leaks. It may be an easily identifiable problem, such as a faulty pan gasket or a filler tube.

    2

    Look at your transmission filler tube. It may have leaking fluid dripping, due to overfilling, a faulty vent or perhaps a dirty filter.

    3

    Check the transmission fluid. If it's black or murky, or smells bad, you may have an overheating transmission or low transmission fluid levels.

    4

    Pay attention to the sounds of your car. If you hear a high-pitched or whining sound coming from the engine while you are driving, it may mean that you have low transmission fluid or even a dirty, clogged transmission filter.

    5

    Be mindful of difficult or jerky gear shifting. This may be the result of low transmission fluid, a clogged transmission filter or problems within the gear shaft.

How to Stop Condensation Under the Car Mat

Condensation under your car's floor mats is a two-part problem with a single solution. Heat under your floor mat comes from the exhaust pipes, and causes moisture trapped in the carpet to steam and collect on the bottom of the mat. The moisture under your carpet has to come from somewhere and that somewhere is almost undoubtedly the air-conditioning system. Normally, condensation in your AC system exits through a small drain tube in the bottom of the vehicle, but over time that drain tube can get clogged and cause water to backflow into your car interior.

Instructions

    1

    Kick a set of wheel chocks in behind your rear wheels. Slide a jack under the front of your vehicle, center it on the frame and lift the car enough so that you can crawl underneath. Secure the frame on jack stands and slide underneath.

    2

    Look for your air-conditioning system drain tube under the passenger-side of the vehicle where the bulkhead meets the floor. The drain tube varies by vehicle; some use a 1/4-inch diameter hard plastic tube, others use a large rubber tube. Some tubes stick straight out of the floor, others are wound up in a semi-circle and still others are recessed into the floorboard and surrounded by a concave opening.

    3

    Clean the tip of the tube out with your screwdriver, hitting it with a quick spray from a garden hose to dislodge any encrusted dirt. Once you have the surface dirt out, straighten out a coat hanger and push it into the tube. If the spiral ends of the wire will fit into your tube, then you're in luck; this screw-shaped spiral acts like a Roto-Rooter to remove clogs. If it won't fit, snip off the spiral and push the wire through.

    4

    Work the wire up the tube in a back-and-forth motion to knock any clogs loose and then pull the wire out from time to time to remove the debris. If you were able to fit the spiral wire into the tube, turn the wire in a clockwise direction to "screw" the spiral through any clogs. The tube should be about 12 to 24 inches long; once you get that far in, you may hear a muted tap as the wire contacts the bottom of the heat exchanger.

    5

    Pull the wire out, drop the car down off the jack stands and start it. Turn the AC on full and allow it to run. Within a few minutes, you should see water start to drip out of the drain tube. To finish the job, take the car to you local car wash and use a wet-dry vacuum cleaner to pull the remaining moisture out of the carpet. Leave the mats out for at least a week to give the carpet time to dry.

Senin, 12 Juli 2010

How to Test Engine Sensors

How to Test Engine Sensors

Car engines are being controlled more and more by electronics. The mechanical governor of the past has been replaced by the electronic control module and sensors. These components work together to improve engine performance and to reduce harmful emissions. The electronic control module monitors these sensor signals and can diagnose when a sensor has failed. The electronic control module will display a specific diagnostic code for that sensor. These codes can be retrieved with the use of a diagnostic tool. Once the code has been retrieved, test the sensor to determine if the sensor has actually failed.

Instructions

Engine Harness and Connection Testing

    1

    Turn off the key switch and open the hood. Verify that the battery is free of corrosion, dirt and debris. If corrosion is found on the battery terminal, use baking soda and a small wire brush to remove the corrosion.

    2

    Inspect the engine harness to verify that it is free of corrosion, abrasion and damage. If damage is found, use electrical tape to temporarily repair the harness. Replace the harness if needed.

    3

    Inspect all of the electrical connections. Verify that the connection to the electronic control module and sensor is tight and secure.

Pressure Sensor Testing

    4

    Turn off the key switch. Disconnect the suspect pressure sensor from the engine harness. Remove the sensor from the pressure port.

    5

    Refer to the engine electrical schematic and remove the signal wire from the sensor electrical connector. Reconnect the sensor to the engine harness.

    6

    Turn on the key switch. Use the digital volt meter to measure the sensor output. Place the positive probe on the signal wire and place the negative probe on a clean chassis ground.

    7

    Refer to the engine schematic or engine manual to verify the sensor pressure range. Gradually apply a pressure to the sensor while monitoring the sensor output voltage. The voltage should change from approximately 0.5 volts, to 4.5 volts.

Temperature Sensor Testing

    8

    Turn off the key switch. Disconnect the temperature sensor from the engine harness. Remove the sensor from the engine port.

    9

    Refer to the engine electrical schematic and remove the signal wire from the sensor electrical connector. Reconnect the sensor to the engine harness.

    10

    Turn on the key switch. Measure the sensor output with the digital volt meter. Place the positive probe on the signal wire and place the negative probe on a clean chassis ground.

    11

    Gradually apply heat to the sensor while monitoring the sensor output voltage. The voltage should change from about 0.5 volts, to 4.5 volts.

Throttle Position Sensor Testing

    12

    Turn off the key switch. Disconnect the throttle sensor from the engine harness. Leave the sensor connected to the throttle assembly.

    13

    Refer to the engine electrical schematic and remove the signal wire from the sensor electrical connector. Reconnect the sensor to the engine harness.

    14

    Turn on the key switch. Measure the sensor output with the digital volt meter. Place the positive probe on the signal wire and place the negative probe on a clean chassis ground.

    15

    Move the throttle while monitoring the sensor output. The voltage should change from about 0.5 volts at low idle to 4.5 volts at full throttle.

1995 BMW 540I Troubleshooting

The 1995 BMW 540i was a large sedan based on the E39 platform. It was a rear-wheel drive German import powered by a V-8 engine that generated 282 horsepower. It had fully independent suspension in the front and back. Unfortunately the 540 did not escape the fuel pump problems that occurred in all BMW engines of the 90s. In addition the BMW V-8s were not built to last, and often required complete replacement after 100,000 miles.

Instructions

    1

    Look at the suspension setup in each wheel well. The 540 mounts coilovers to deal with the greater weight of the V-8 and the accompanying inertia. Look at the coil springs for any cracks and to see if they have sheared in half. Look at the hydraulic piston in the middle of the coil for any signs that it is leaking oil. Feel the control arms for any cracks that would indicate pending suspension failure. Do not drive any car with broken suspension components; call a mechanic to flat bed it.

    2

    Look under the 540 for any signs of gas leaks. Open the engine bay and examine the gas pump on the side of the engine bay. Look for any leaks where the gas line connects to the gas pump. Start the car and listen for all the cylinders to fire; it should should like a rumble. If it sounds like only some of the cylinders are firing or if it sounds weak like a four-cylinder, then the pump may be failing.

    3

    Shift the car into drive and listen for the engine to rev. The V-8 should roar when revving, not cough. Coughing could indicate a damaged exhaust or intake manifold. Press down on the brake; the brake should feel stiff. If the brake pedal has variable resistance or if it rumbles, then the brake fluid needs to be flushed and the brakes changed. The brake pads may be bad and the brake discs may be warped. Do not drive a car with malfunctioning brakes.