By Chilton

The Ford Focus is an economical car. First generation models can get upwards of 30 miles per gallon, and their lifetime maintenance costs tend to be low. That said, you can save even more on service and maintenance by doing some simple tasks yourself. Replacing the fuel filter in a Ford Focus is one of those money-saving tasks.
You'll generally want to change the fuel filter every 30,000 miles — so maybe every two or so years, depending on your driving volume. The filter is replaceable on 2000-05 models. In 2009, Ford started using a permanent filter which is part of the fuel pump module.
To change the fuel filter, you'll need a replacement fuel filter and a socket wrench set. You’ll also need a good quality floor jack and jackstands, or a set of good quality drive-on ramps.
Put on disposable nitrile or neoprene gloves since gasoline is tough on skin; wear safety goggles to avoid getting gasoline in your eyes; and have handy some sort of catch can, since there will be some gasoline in the old filter.
Warning! Before starting any work on or near the fuel system, remember, never smoke anywhere near the fuel system or have any type of flame or spark near it! Gasoline is highly flammable. Be prepared for fuel spills, clean them up immediately and dispose of gasoline-soaked towels safely. Materials with gasoline on them can catch fire spontaneously.
The fuel system is pressurized, so you’ll have to relieve that pressure before you open any part of the fuel system. Find the fuse box. Inside the fuse box, locate the fuel pump fuse. You will be able to find it based on the diagram on the fuse box cover or by consulting Chilton’s online database. Remove the fuel pump fuse.
Start the engine and allow it to run until it stalls. Crank it for 5 seconds more to make sure all pressure is relieved. It may not start at all. In either case, this will relieve the fuel pressure.
The fuel filter should be on the passenger side, in the area of the rear suspension, near the leading edge of the fuel tank. If you’re using a floor jack and jackstands, place the automatic transaxle in Park or the manual transaxle in First gear. Firmly set the parking brake, lift the passenger’s side of the car at the jack point, which should be indicated by an arrow or triangle shape underneath the car. Once elevated, place the jack stands under the car to ensure it doesn't fall or slip. If you’re using ramps, drive onto the ramps until the rear of the car is securely supported. Place the automatic transaxle in Park or the manual transaxle in First gear. Firmly set the parking brake.
This is the evaporative emission tube used on some 2000-04 Ford Focus models. Disconnect this first.
This is the fuel filter location and fuel lines (arrows) for the 2000-04 Ford Focus models.
This is the fuel filter location and the fuel lines (see arrows) for the 2005 Ford Focus.
The fuel lines (see arrows) connect to the fuel filter. On 2000-04 models, there can be 4 types of quick-release couplings:
On 2005 models, disconnect the fuel line by depressing this type of quick release tab:
2005 Ford Focus fuel line quick release tab.
Depending on the model year, there will also be an evaporative emissions vapor line. Disconnect that as well.
The fuel filter will be secured to the car using a bracket. Using a wrench, remove the fuel filter bracket. At this point, you can easily remove the fuel filter.
This is the fuel filter bracket bolt for the 2005 Ford Focus.
Place the new filter in the bracket and bolt it in place. Make sure the filter is facing the correct direction. New filters usually have an arrow to note this.
Align the fuel tube fittings and press them together until they seat. It will make a click sound. Then test by pulling on the fittings to make sure they are securely connected.
Reconnect the battery ground cable and re-insert the fuel pump fuse.
You can turn the car on and check the area under the fuel filter for any leaks. If you find leaks, turn the car off, remove the fuel pump fuse and disconnect the ground cable. Investigate the source of leaks, such as a loose connection or improperly fitted fuel filter.
When everything looks good, carefully lower the car from the jackstands or drive it off the ramps.
If there are no leaks, then congratulations. You've successfully replaced your fuel filter. When you have questions, subscribe to ChiltonDIY for detailed instructions, images, technical service bulletins and specifications to assist you in maintaining, servicing and repairing your Ford Focus.

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