Whatever you do, don’t just throw it in park and hop out of the cab. You might be thinking we’re a bunch of nags, but you wouldn’t believe how many people have been crushed when their machinery started to roll away. To avoid this disaster, make sure your machine is parked on a level surface before you begin.
Block off your tires so that the machine won’t be able to roll away if the parking brake fails. This could happen if your machine has been sitting around for a while, because moisture can get into the brake system and cause it to rust.
In addition to blocking off your tires, use wheel chocks as well. These are small wedges that keep the wheels from rolling even if they aren’t blocked by something heavy.

Remove the three 10mm bolts and two 10mm nuts that hold down the right side panel. The nuts are found on the inside of the engine compartment, and one is under a plastic cover to keep dirt from getting into it.
Remove the bolts holding down the battery box cover by removing the two 8mm bolts and two 10mm nuts. The nuts are threaded onto studs that protrude through the frame.
Remove the bolt holding down the airbox. It is a single 8mm bolt at the back of the airbox.

This fuel filter replacement is specific to the Mercury Villager, but the fuel filter is located in the same area on many Nissan vehicles.
Park your car in a safe place, with the handbrake on and the engine off. You will be working with flammable materials so make sure there are no sources of ignition in the area.
Open your hood, and locate the air filter housing box. It is directly behind the engine and right above a black rectangular box (the charcoal canister). The fuel filter is attached to this box by two hose clamps.

We recommend that the fuel line be replaced at this time. The line is not expensive and it’s much easier to change it now than wait until you have problems. In our experience, fuel lines are always suspect on these cars because of the difficulty in getting them out of the tank. If you are going to reuse the old line, make sure it’s not kinked or bent and that there is no rust or dirt in the ends. It should go without saying, but make sure your hands are clean when installing this part.
The fuel line is held in place by a small clip about 3 inches from the tank. Use your needle nose pliers to release the clip. If there is any resistance, look closely at the clip – it may not be fully released.

Unscrew the lid from the filter. The lid is connected to a small filter inside. You need to unscrew that as well.
The connection to the fuel filter is located on top of the engine block, right next to the air intake and fuel injectors. You need to unscrew this lid and drain out all of the oil.
Be careful not to damage the small connections when you unscrew this lid, they are easily broken if you are not gentle.

To replace the filter element, remove the metal holding plate which will expose and allow you to remove the old filter.
The metal holding plate will be on one side of the filter housing. It is important to note that some filters are held in place by four screws or wing nuts while others are held in place by two screws or wing nuts. The housing has arrows pointing towards the screws or wing nuts that need to be removed.
If you live in a hard water area, you may also have a sediment pre-filter installed inside your system as well. Be sure to clean out this sediment pre-filter first before removing your original filter element.

To return the fuel filter lid and hose clamp, simply follow the above steps in reverse order.
1. Use your fingers to place the fuel filter lid onto the fuel filter assembly. Rotate the lid clockwise until it is firmly in place.
2. Replace the metal fuel line onto the fuel filter assembly. Use your fingers to secure it into place and then tighten it with an adjustable wrench (if necessary).
3. Replace the hose clamp onto the rubber fuel line and use your flat-head screwdriver to secure it in place.

Make sure to change your fuel filter on a regular basis. This is the secret to keeping your car in good condition. Look at the owner’s manual and find the recommended mileage interval for changing your fuel filter. Just clean it up and replace it with a new one according to the manufacturer’s guidelines.
Check your owner’s manual and look for the recommended oil change interval. You get better gas mileage if you wait between oil changes, but you are taking a big chance by not changing this part of your car regularly. If you do not take care of it when needed, your car might stop working much earlier than expected.