The fuel filter is designed to keep contaminants out of the fuel system. The fuel injector sprays a fine mist of fuel into the cylinder moments before the spark is ignited. The orifices in the injector are very small and can become clogged with dirt and metal debris in the fuel. Knowing the symptoms of a dirty fuel filter may help you eliminate costly repairs.
Engine Runs Rough
The engine will run rough when it is not getting enough fuel into the cylinder. A partially blocked fuel filter will allow some fuel into the cylinder to keep it running but not enough to keep it running smoothly.
An engine will stall when the demand on the fuel system exceeds the fuel supplied to the cylinder. Accelerating from a stop may cause the engine to stall because the engine cannot produce enough power to keep the car moving.
Engine Cranks but Won't Start
A blocked fuel filter will limit the amount of fuel that is injected into the cylinder. If the cylinder is not getting enough fuel, the engine will not start.