The 1990 Chevy 1500 features the squared body design and a 4.3 liter, V6 engine. The vehicle was introduced as a fuel economy vehicle without sacrificing the hauling and towing capabilities. Troubleshooting engine problems is achieved through listening and feeling for changes in the performance. Troubleshooting breakdowns is achieved by using the process of elimination to separate functioning parts from failing parts. The vehicle does not use a computer diagnostics system and owners can make repairs without an electronic reader.
Turn the key and test the battery by turning on the interior light and radio. If the lights are weak and they flutter while attempting to start, charge the battery with jumper cables and a running vehicle. If the battery does not hold the charge, replace it with a new one. Replace the alternator if the battery continues to lose the charge.2
Turn the key to start the engine. If the engine cranks but does not fire, replace the spark plugs. If the plugs do not help, clean the fuel injectors. If the truck continues to fail, replace the fuel pump.3
Replace the starter if the battery and alternator are good but the engine will not crank when you turn the key. The Chevy truck is likely to require a new tarter every three or four years. The starter is especially likely to fail in cold environments.4
Test drive the truck on a flat surface and vary the speed to test the transmission. If the transmission is in bad condition it will grind and jump gears. The transmission should shift smoothly without excessive revving and overworking.5
Feel for pulling and vibrating as you drive. The four-wheel drive lockers will stick on the hubs if the transfer case malfunctions. Shift the vehicle between two wheel drive and four-wheel drive several times release the lockers from the hubs. Have the transfer case serviced if the four wheel will not release.