Replacing The Fuel Pump In A Jeep Wrangler (2004)

Replacing the fuel pump on a 2004 Jeep Wrangler involves several steps and can be done at home with the right tools and safety precautions. The fuel pump is responsible for delivering fuel from the tank to the injectors, and issues with the pump can cause engine problems or even prevent the car from starting. Before beginning, it is important to disconnect the battery to reduce the risk of fire. The process involves depressurizing the fuel system, disconnecting the tank lines, lowering the fuel tank, removing the old pump, installing the new pump, and reconnecting the fuel lines and battery. Some recommend replacing the entire fuel pump assembly, which includes the pump and the filter, and it is also advised to replace the fuel filters at the same time. Working with the fuel system can be dangerous, so taking all necessary precautions is crucial.

Disconnect the battery

Disconnecting the battery is the first step in replacing the fuel pump on a 2004 Jeep Wrangler. This is a crucial safety measure to reduce the chance of a fire when working on fuel system repairs.

To disconnect the battery, locate the negative terminal, which is usually marked with a '-' symbol or a black cover. Loosen the nut or bolt that secures the cable to the terminal using an appropriate-sized wrench or socket. Do not allow the wrench or socket to touch any other metal parts of the car, as this could result in a short circuit. Once the nut or bolt is loose, carefully detach the cable from the battery terminal.

It is important to note that modern car batteries can still hold a charge even when the vehicle is turned off. To prevent any accidental short circuits or electrical shocks, it is recommended to wear insulated gloves and cover the terminal with a piece of tape or a plastic bag.

Additionally, some vehicles may have a retaining clip or clamp that holds the battery cable in place. If this is the case, use a flat-head screwdriver to carefully pry or lever the clip away from the cable before attempting to loosen the nut or bolt. Ensure that you do not damage the cable or the clip during this process.

After the cable is detached, it is a good idea to clean the battery terminal using a wire brush or a mixture of baking soda and water to remove any corrosion. This will help ensure a good connection when the battery is reconnected.

Finally, make sure to keep the disconnected battery cable away from the battery and any metal parts of the car to prevent accidental contact and the risk of electrical sparks. You can place the cable on a piece of insulation or rubber to ensure it stays put.

Remove the gas tank

To remove the gas tank from a 2004 Jeep Wrangler, you will need to first depressurise the fuel system. Remove the fuel pump relay from the fuse box in the engine bay, then attempt to start the Jeep a few times to depressurise the system. Next, disconnect the negative lead on the battery.

Now, you need to remove the gas filler cap. There will be four screws on the outside and four on the inside. You may need to remove the gas cap to drop the tank, but try to keep it on for as long as possible to prevent debris from getting inside.

The next step is to disconnect the tank lines from the Jeep, so you can lower the tank. You are looking for three lines: two fuel lines and an EVAP line. Disconnect each of the three lines, as well as the electrical connection to the fuel pump.

Now, you can start to remove the skid plate. There will be four nuts on the rear portion and three on the front. Place a jack under the tank and jack it up enough to support the tank while you remove the nuts from the skid plate.

Slowly lower the fuel tank, feeding the filler cap/neck and the other two lines down as you go. Take your time with this step, as it can be easy to rip a fuel line. Once the tank is lowered, you can drag it out from under the Jeep.

Make sure you clean the top of the tank before removing the existing pump, to prevent debris from falling into the tank.

Disconnect the fuel lines

Disconnecting the fuel lines is a crucial step in replacing the fuel pump on a 2004 Jeep Wrangler. Here is a detailed guide on how to do it:

Before beginning, ensure that you have depressurised the fuel system and disconnected the negative lead on the battery. This is important for safety reasons and will make the process easier.

Now, locate the three lines that need to be disconnected: two fuel lines and an EVAP line. These lines are usually found on the driver's side of the Jeep, above the rear shock towards the bumper. You may need to lower the tank partially to access them. Using a pair of needle-nose pliers and a small flat screwdriver, carefully pop off the retaining link from the plastic fitting. Once the retainer is removed, the fuel lines can be separated easily.

When disconnecting the fuel lines, it is important to be gentle to avoid damaging them. Mark each line you disconnect to ensure you know which line connects where when reassembling. You can use coloured electrical tape to mark each end of the disconnected lines.

After disconnecting the fuel lines, you will also need to disconnect the electrical connection to the fuel pump itself. This is usually located with the fuel lines. Once all the lines and connections are disconnected, you can move on to removing the skid plate and lowering the fuel tank.

Take your time and work carefully to avoid any spills or damage to the fuel lines and connections. It is also important to work in a well-ventilated area and take the necessary precautions when handling fuel lines, as there may be some fuel spillage during the process.

Now that you have disconnected the fuel lines, you can continue with the next steps of replacing the fuel pump on your 2004 Jeep Wrangler. Remember to refer to a qualified mechanic or a detailed guide for the full procedure, as replacing a fuel pump can be a complex task.

Remove the old fuel pump

To remove the old fuel pump from your 2004 Jeep Wrangler, you will need to perform the following steps:

Firstly, depressurise the fuel system by pulling the Fuel Pump Relay out of the fuse box, located in the engine bay on the passenger's side. Then, attempt to start the Jeep a couple of times to release the pressure. Next, locate the pressure valve next to the fuel rail on the driver's side of the engine, and use a screwdriver to press down on the valve to further relieve the pressure.

Now, disconnect the negative lead on the battery. Then, unscrew the screws holding the gas filler cap, both on the outside along the body and on the inside around the cap itself.

The next step is to disconnect the tank lines from the Jeep to lower the tank. You are looking for three lines: two fuel lines and an EVAP line. Disconnect each of these lines, as well as the electrical connection to the fuel pump.

Now, start removing the skid plate. There will be four nuts on the rear portion of the skid plate and three nuts on the front. Loosen these nuts before placing a jack under the tank to support it while you remove the nuts completely.

Slowly lower the fuel tank, being careful to feed the filler cap/neck along with the other lines down with the tank. Take your time with this step to avoid ripping any fuel lines. Once the tank is lowered, drag it out from under the Jeep so you can work on it easily.

Before removing the old fuel pump, clean the top of the tank to avoid any debris falling into the tank. Then, use a strap wrench to remove the retaining ring that holds the fuel pump assembly in place. The ring is plastic and quite tight, so you may need to use a hammer and screwdriver to tap it and break it free. Once the ring is removed, carefully remove the fuel pump assembly, being mindful of any fuel spillage.

At this point, you have successfully removed the old fuel pump and can now install the new one.

Install the new fuel pump

To install the new fuel pump, you will need to follow these steps:

• Clean the top of the fuel tank to ensure no debris falls into the tank when the new pump is installed.
• Take a quick picture of the old fuel pump's position and orientation to use as a reference for installing the new pump.
• Using a strap wrench, remove the retaining ring that holds the old fuel pump in place. It is plastic and tight, so use caution when removing it. The ring's threads are likely to be left-handed, so turn it anti-clockwise to loosen it. Some force may be required, and a mallet and screwdriver can be used to tap the ring and help loosen it.
• Carefully remove the old fuel pump assembly, being mindful that some fuel will spill. Try to manipulate the assembly to minimise the amount of fuel spilled.
• Discard the old pump and the old rubber gasket between the pump and the fuel tank.
• Take the new rubber gasket and fit it onto the tank. Ensure it is sandwiched between the lip of the new pump and the rim of the tank.
• Install the new fuel pump assembly into the tank. It should fit fairly easily and may require some manipulation to get it into position. Ensure the pressure regulator is pointed in the 10-11 o'clock position.
• Install the new plastic retaining ring. This can be tricky, and patience is required to avoid cross-threading. Use the strap wrench to tighten the ring to the same torque as the old one.
• Reconnect the fuel tank to the Jeep, following the reverse order of the removal process. Be extremely careful when raising the tank to avoid damaging the electrical connection. Connect all the colour-coded fuel lines before tightening the hardware on the skid plate to allow for some wiggle room.
• Double-check that all the lines are reconnected, including the electrical connection to the fuel pump.
• Reconnect the negative lead of the battery.
• Turn the key as far as you can without cranking the engine, and do this a few times. You may hear the new fuel pump turn on.
• Try to start the engine. It should crank right up without hesitation.

Frequently asked questions