Changing the fuel filter in your Mark VII is an easy way to prevent fuel system problems. A clogged fuel filter can cause performance issues just as worn spark plugs and ignition parts can.  Check your maintenance manual, the recommended replacement interval is every 30,000 miles.

NOTE: While changing the fuel filter, make sure there are no open flames, do not smoke, and do not hang an incandescent light nearby.



TOOLS YOU WILL NEED

• Flat blade screwdriver

LET'S GET STARTED

 
The fuel filter is located under the car, just in front of the right rear wheel. I found it easier to use a lift and raise the car in the air. HOWEVER, before you raise the car off the ground, remember to TURN THE AIR SUSPENSION SWITCH to the OFF POSITION. If you must do this on the ground, don’t forget to put a jack stand under the car for added safety!

Spillage of gasoline will occur when changing the fuel filter. To depressurize the fuel system, install an EFI fuel pressure gauge to the Schrader Valve located on the engine fuel rail assembly. Open the valve and drain fuel into a suitable container. Do not do this while the engine is hot. Remove the gauge when the system is depressurized and replace the cap.



Once the system is depressurized, we can now remove the old fuel filter with minimal fuel spillage. Loosen the clamp around the fuel filter with a flat head screw driver. Then place a drip pan under the fuel filter to catch the spillage. Pry down and remove the clips holding the fuel lines to the filter. Pay attention how these clips were inserted through the hose fittings; you must put the new clips back in the same way. Pull the “IN” line away from the filter, then pull the “OUT” line from the filter. Use caution, fuel will be dripping from the hoses and filter. Slide the old filter out of the bracket towards the rocker.

 

Typically a new fuel filter comes with new retaining clips. Simply slide the new filter into the bracket, slip the “IN” hose all the way onto the filter nipple and insert the retaining clip. Next, slide the “OUT” hose onto the nipple and secure with the retaining clip. Gently pull on the hoses to make sure they are secure. Tighten the clamp around the filter and double check the fuel hoses to make sure they are secure.

Lower the car, start the engine, and check for leaks.