Replacing Fuel Filter In Qx4: Step-By-Step Guide

Changing the fuel filter on an Infiniti QX4 is a maintenance task that can be performed at home with relative ease. The fuel filter is located above the rear differential, tucked away towards the bottom of the floor panelling. The procedure begins with opening the fusebox and removing the fuel pump fuse, before starting the car and waiting for the engine to die, ensuring that fuel is completely out of the system. The next steps involve crawling under the rear of the vehicle to locate the fuel filter, removing the mounting bracket, and then the clamps holding the fuel lines to the filter. It is important to note the direction of fuel flow before completely removing the old filter. Finally, a new filter can be installed, ensuring proper direction, and the mounting bracket and fuse can be replaced before starting the vehicle.

Depressurise the fuel system

Depressurising the fuel system on your Infiniti QX4 is a crucial step in changing the fuel filter. Here is a detailed, step-by-step guide on how to safely depressurise the fuel system:

Firstly, locate the fusebox and remove the fuel pump fuse. It is usually in the middle of the third column, but you can double-check its position by referring to the chart printed on the side of the fusebox housing. Once you have identified the correct fuse, pull it out.

Now, turn on the ignition and start the car. The engine will eventually die due to a lack of fuel. At this point, start the car again and repeat the process until you are certain that all the fuel is out of the system. This step is crucial for safety, as it ensures that pressure is released from the fuel lines.

After confirming that the fuel system is entirely depressurised, you can safely proceed with the next steps in changing the fuel filter. It is important to exercise caution when working with any fuel system, as gasoline is highly flammable.

Remember to refer to the owner's manual or a trusted mechanic if you have any questions or concerns during the process. Safety should always be the top priority when working on your vehicle.

Remove the old fuel filter

To remove the old fuel filter from your Infiniti QX4, follow these steps:

Firstly, relieve the fuel pressure. Do this by removing the 15-amp fuse located on the interior fuse panel. You can find this on the bottom left side of the steering wheel, behind the coin tray. Start the car and wait for the engine to die. Repeat this process until you are sure that the fuel is completely out of the system.

Now, crawl under the rear of your truck and locate the fuel filter. It is situated above the rear differential, tucked away towards the bottom of the floor panelling. Take a Phillips screwdriver or a 10mm wrench to remove the mounting bracket.

Next, remove the clamps holding the fuel lines to each end of the filter. Pay attention to the direction of the fuel flow before removing the filter completely.

If your filter is particularly stubborn and doesn't come off easily, try rotating or "twisting" the lines to break the seal. Rock the filter back and forth to help pull it off. Ensure you have loosened the clamps enough to remove the filter.

Now you are ready to install the new fuel filter, following the above steps in reverse.

Install a new fuel filter

To install a new fuel filter in your Infiniti QX4, follow these steps:

Firstly, relieve the fuel pressure. Do this by removing the 15-amp fuse located on the interior fuse panel. You can find this on the bottom left side of the steering wheel, behind the coin tray. Start the car and wait for it to die. Repeat this process until you are sure that the fuel system is depressurised.

Next, locate the fuel filter. It is found above the rear differential, tucked away towards the bottom of the floor panelling. You will need to crawl under the rear of the truck to access it.

Now, take a Phillips screwdriver or a 10mm wrench to remove the mounting bracket. Then, remove the clamps holding the fuel lines to each end of the filter. Pay attention to the direction of the fuel flow before removing the filter completely.

Finally, install the new fuel filter, ensuring it is facing the correct direction. Reattach the line clamps, bracket, and fuse, and start the vehicle. The system may need a few extra cranks to re-pressurise.

It is important to note that a clogged fuel filter can cause serious loss of performance and may eventually prevent the car from starting. Therefore, it is recommended to replace the fuel filter per the manufacturer's scheduled maintenance.

Check for leaks

Once you have replaced the fuel filter, it is important to check for leaks. This is because any gas leak can become extremely dangerous if not dealt with. Leaking fuel can cause worsening fuel economy, and your vehicle may be susceptible to fire or an explosion.

Firstly, you should inspect the ground underneath the gas tank to see if gasoline has pooled under the tank. If there is a leak, you should be able to notice it underneath the rear of the vehicle, accompanied by a noticeable smell. It is important to check that the liquid is indeed gasoline.

If there is a leak, you should then inspect the tank itself to identify the source of the leak. If the tank is corroded, you may be able to repair it without replacing it. If the tank is punctured, it will most likely need to be replaced.

If the tank needs to be replaced, you will need to drain the old tank, disconnect the original fuel lines, remove the straps holding the tank, and drop it. You should then install the new tank, ensuring that all the appropriate parts are reconnected. Finally, you should add fuel to the tank and start the vehicle to make sure the fuel system is working properly.

Repressurise the fuel system

To repressurise the fuel system of your QX4, you will need to turn the key in the ignition to just before the engine cranks over. Do this 5-6 times to build up pressure in the fuel system.

Now, you can try to turn over the engine and start the car. It may take a few attempts for the car to start, so be patient. If the car does not start after several attempts, you may need to troubleshoot.

Once the car is running, check for any leaks in the fuel lines.

Frequently asked questions