Fuel Filter: Description and Operation

Typical Fuel Filter:

Clean fuel is extremely important in a fuel injection system because of the small orifice in the injector tip through which fuel must pass. Most injection systems use three forms of filters. The first is a fuel strainer or filter of woven plastic attached to the fuel pump inlet. This prevents contamination from entering the fuel line and separates water from the fuel. The filter is self-cleaning and requires no maintenance. If a fuel restriction occurs at this point, the tank contains too much sediment or moisture and should be removed and cleaned.
Additional filtration is provided by a high capacity Inline filter to remove contamination larger than 20 microns (0.0050 inch). This filter is designed to last the life of the vehicle. The final line of defense against fuel contamination is in the fuel injector. Each injector contains its own inlet filter screen to prevent contamination from reaching the tip.