Regarding Fuel Filter - Under vehicle, driver side, below seating area, front
of fuel tank, mounted on chassis in fuel line.
A device located in the fuel line to remove impurities from the fuel before it enters the carburetor or injector system.
Fuel filters can be located in a fuel line, in the tank, in a
carburetor, or in any combination of these. A carburetor often has a
filter behind the fitting at its fuel inlet.
A carburetor inlet filter. Courtesy of General Motors Corporation, Service Technology Group.
Fuel filters that are installed on the outlet side of a fuel pump are called outlet filters.
An external fule filter. Courtesy of General Motors Corporation, Service Technology Group.
Engine heat causes fuel to vaporize, which can result in vapor lock
in the filter. Some fuel filters have vapor return lines to allow for
expanding vapors and fuel to return to the tank.
A fuel filter with a vapor return outlet. Courtesy of AlliedSignal Automotive Aftermarket.
Fuel injection systems require larger, heavier duty filters than
carburetors. They filter out smaller particles of dirt while still
allowing the pump to supply a substantial amount of fuel.
Fuel filters and elements are serviced by replacement only. Some
vehicle manufacturers recommend fuel filter replacement at 30,000 miles
(48,000 km). Always replace the fuel filter at the vehicle
manufacturer's recommended mileage.
The fuel filter replacement procedure varies depending on the make
and year of the vehicle and the type of fuel system. Always follow the
filter replacement procedure in the appropriate service manual. The
photo sequence below shows a typical procedure for relieving fuel
pressure and removing a fuel filter.
Removing a Fuel Filter on an EFI Vehicle
Disconnect the negative cable at the battery.
Loosen the fuel tank filler cap to relieve any fuel tank vapor press
Connect the fuel pressure gauge to the Schrader valve.
Install the free end of the gauge bleed hose into an approved gasoline
container, and open the gauge bleed valve to relieve the fuel pressure.