Changing the fuel filter is not an easy thing. But if you have mastered the ability, it’s also not difficult. To sum up, there are 3 main parts as following to replace the fuel filter. Please pay attention that the following guide is applicable to gasoline engine vehicles only. Because changing the diesel fuel filters is more complex. Diesel cars and trucks typically have much larger fuel filters, and the entire fuel system is much more complex. The fuel systems of diesel engines are also under greater pressure, with modern public rail systems generating more than 1,000 bars. Accidentally releasing such high levels of pressure can lead to injury. Thus it’s better to ask the professionals for help.

Things in need when replacing the gasoline engine vehicle

You have to buy a new fuel filter that is suitable for your vehicle. In addition, you need some tools including a jack, jack stands, screwdrivers, open-end wrenches, socket wrench, rag, a bowl to catch the fuel that might spill out, a piece of cloth, and protective gear such as goggles and gloves.

The following guide is applicable to gasoline engine vehicles only! As the gasoline is highly flammable, choose a well-ventilated place and keep away the objects that are easy to spark or flame. Lear more about fuel filter types.

Part I: Relieving the Pressure in the Fuel System & Expelling Fuel

Step 1 – Find where your vehicle’s fuse box is

Before you change the fuel filter, you need to relieve the pressure in the fuel system at first. To relieve the pressure on the fuel system, you need to run the vehicle without a fuel pump for a short period of time. And the attempt to locate the fuse box that contains the fuel pump is to prevent the fuel pump from starting with the engine.

Most cars have fuse boxes inside and under the hood. The fuel pump fuse is usually located in the fuse box inside the car. You can also refer to your vehicle’s owner’s manual to make sure where the appropriate fuse box is. If you don’t have a user manual, try the automaker’s website or the customer service.

Step 2 – Remove the fuel pump fuse

Removing the fuse will disconnect the power supply to the fuel pump and relieve the pressure in the fuel lines. Without the fuse, the fuel pump won’t work while you start the engine. But remember that there is still fuel and pressure in the fuel line from the rear to the front.

You have known the location of the fuse box in the first step, then what you have to do is to find the fuse according to the diagram on the fuse box cover or the owner’s manual. Next, remove the fuse with sharp-nosed pliers or plastic tweezers.

fuel pump fuse

Step 3 – Secure the vehicle by ensuring the vehicle is not in gear

Although the engine will not get a fresh supply of fuel from the tank, there is still enough fuel in the line to get it up and running briefly. If the car is in left gear, it can move. Thus you have to secure the vehicle by ensuring it is not in gear.

For the automatic vehicle, ensure that it is parked in the parking lot. For vehicles that use manual transmission, make sure that the parking brake is activated when the vehicle is in neutral.

Step 4 – Start and run the engine for a few minutes before shutting it off

Get the engine up and running for a few minutes. This removes any remaining fuel and releases pressure in the fuel line. This should happen in a minute or two because the fuel pump is not working. Without the action of a fuel pump, the pressure in the fuel line will be quickly released.

Depending on the vehicle’s fuel system and average fuel consumption, the running time of a vehicle without a pump can vary greatly. However, it does not need to run the engine to death. Instead, just let it run for a minute or two, then turn the key off. Keeping the engine running until it stalls may make it difficult to start again.

Insert the key into the ignition switch and turn it to start. When the engine consumes the remaining fuel in the fuel system past the fuel pump, the engine should start easily. If the engine turns over and then spouts fuel, it’s probably because there isn’t enough pressure in the line to force the fuel into the engine. If the engine shuts down, the fuel pressure will be fully relieved.

Step 5 – Turn off the engine & Re-insert the fuel pump fuse

When the pressure is relieved from the fuel system and switch off the engine, you can re-insert the fuel pump fuse. Place the cover back on the fuse box and return any trim you may need to remove to access it. But remember to ensure the vehicle is off before re-inserting the fuse. Also, do not start the engine again.

Part II – Removing the Old Fuel Filter

Step 6 – Find and disconnect the negative terminal of the battery

Disconnecting the battery is a safety precaution to prevent the engine from starting while you are working underneath the vehicle.

Use a hand or socket wrench to loosen the nut that holds the cable onto the negative terminal. There is no need to remove the nut completely. Just plug the negative wire to the side of the battery to ensure that it does not accidentally touch the terminal of the battery.

Step 7 – Find the position of the fuel filter

Refer to your owner’s manual is the direct way to find the position of the fuel filter. In general, there are 2 common locations. The first is along the fuel line on the bottom of the car, just past the fuel pump. The second is in the engine bay on the line leading to the fuel rail.

Step 8 – Jack up the vehicle if necessary

If the fuel filter is on the bottom of your car, for easy access, jack up the car. Be careful to use the jack stands for safety reasons. Slide the jack under the car at the specified jack point and then use a pump or twist the handle to lift the car up. Once the vehicle is jacked up, place jack stands beneath it before working under the vehicle. Do not rely on a jack to support the weight of a vehicle you are beneath while working.

Step 9 – Place a container such as a bowl beneath the fuel filter to catch the fuel

There still may be a little fuel left in the line that can spill out when disconnected from the fuel filter, though the pressure in the fuel line is relieved. Place a bowl or bucket under the fuel filter to catch any dripping or flowing fuel. Do not mix fuel with oil or coolant to be recycled. Gasoline should be kept in its own container until it can be discarded to a recycling site. Be careful when using plastic containers to hold gas, as it can corrode some of the plastic and cause leaks.

Step 10 – Remove the clips holding the fuel filter in place

Remove the two plastic clips that secure the fuel filter. Use a screwdriver to do that. The clips should come out without difficulty. Locate the clip on either side of the cylindrical fuel filter and then use a flat-head screwdriver to eject them through the hole. These clips may break, so it is recommended that you replace the clips as you purchase the fuel filter.

how to fuel filter
Change a Fuel Filter

Step 11 – Remove the fuel lines from the filter

Slide the fuel lines on either side to disconnect them from the fuel filter. Then pop the fuel lines off of the nozzles on either end. Make sure the the fuel line is aligned with the container so that spilling gasoline can be collected there. You’d better wear eye protection and gloves in order to protect yourself from the fuel splatter. Besides, try your best not to pour any gas onto the ground.

Step 12 – Remove the fuel filter

The fuel filter may be attached to its outer casing by a metal bracket. When the fuel line is disconnected, you can push the fuel filter to the front of the car and slide out of the bracket. The fuel filter will have a slight bell shape, allowing it to slip out in one direction. If your filter is in a different position on the bracket, you may need to slide it to the back of the car to remove it. And also check to see if there is a bolt or bolts to remove. Some of the fuel filters under the hood may be in bracket with bolts. So those bolts will need to be removed in order to slide out of the filter.

Part III: Mounting a New Fuel Filter

Step 13 – Examine the new fuel filter

In order to prevent to use a wrong filter in your car, examine the new filter to make sure that it is the right one. You can check the inlet diameters, outlet diameters, size and other design features. Try to see that the new fuel filter is identical to the old one. Make sure that their nozzles are the same size and both can fit into the bracket rightly. Using a fuel filter for a different application in your car won’t allow the appropriate volume of fuel to pass through it.

Step 14 – Insert the new fuel filter into the bracket

It’s very easy to slide the new fuel filter into the bracket. The incorrect fuel filter without the right diameter needs force to be pushed. The fuel filter should stop when it is properly positioned, as it should only glide out in one direction. Be careful not to damage the housing of the fuel filter, as this may cause fuel leaks.

fuel filter

Step 15 – Fasten the fuel filter to the fuel line

Slide the fuel line as the same way they were connected to the old filter. When the fuel line is in place on the filter, the sliding plastic clip passes through the hole on the fuel line nozzle to secure the line to the fuel filter. These clips can break easily. If that happens, you may need to replace them.

Step 16 – Lower the vehicle off of the jack stands & Reconnect the negative terminal of the battery

Lift the car with a jack to lighten the jack station, and then slide them out from the beneath of the car. After the jack is retracted, lower the vehicle to the ground by releasing pressure within the jack or by rotating the jack handle counterclockwise, which depends on your jack type. Make sure the jack stands are completely out of the way, otherwise they could damage the vehicle if lowered into them. After the vehicle has landed safely, reconnect the batteries.

Step 17 – Start and run the engine to check fuel leaks

Finally, you can start and run the engine. Run the engine for not more than a few minutes. Make sure there are no leaks in the newly installed filter.

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