You need to change the fuel filter on the 2005 Ford Focus every 60,000 miles or four years, whichever occurs first. The fuel filter on the 2005 model is mounted underneath the car in front of the fuel tank. This makes removing and changing the fuel filter a simple process compared to that of other vehicles. You are still dealing with the high pressure of the fuel system, however, so use caution.
Clean the fittings at both ends of the filter if there is more than a light coat of dust there. Compressed air is one of the best methods.
Relieve the fuel system's pressure by removing the No. 12 fuse from inside the fuse box in the engine compartment, then start the car and let it idle until it dies out.
Inspect the fittings used for the fuel filter. It may use one of two types of quick-connect fittings: a "squeeze" type fitting or a "push clip" type fitting.
Disconnect the squeeze fittings by pressing their locking tangs together. If the fuel lines are connected by push clip fittings, pull out the locking tang and then push the clip through the coupling. Pull the fuel hoses off the filter one at a time; expect fuel to come out.
Loosen the clamp for the fuel filter with a screwdriver, making sure you know the direction the filter faces while installed. Remove the fuel filter from its bracket.
Install the replacement fuel filter to the bracket in the same direction that the old filter faced. Tighten the clamp with the screwdriver.
Push and connect each hose to the fuel filter, making sure each hose is seated against the collar on each fitting and locks in place. Pull on the fittings to ensure they are locked.
Reconnect the fuel pump fuse (the No. 12 fuse) in the fuse box.
