Replacing The Fuel Pump In Your 1999 Jeep Cherokee

Replacing the fuel pump on a 1999 Jeep Cherokee is a moderately complicated job that is best performed by a professional mechanic or dealership service department. The fuel pump module is installed in the top of the fuel tank and will need to be removed and replaced if the electrical fuel pump requires service. Before servicing the fuel pump module, the fuel system pressure must be released, and the fuel tank drained. The cost of replacing a fuel pump on a 1999 Jeep Cherokee is estimated to be between $611 and $1289, including parts and labor.

Disconnect the battery

Disconnecting the battery is the first step when replacing the fuel pump on a 1999 Jeep Cherokee. This is a general safety precaution when working in the engine compartment or with any component of the fuel system.

To disconnect the battery, start by locating the negative (black) battery terminal. Loosen the cable nut and wiggle or pull the cable off the terminal. Be sure to place the cable in an area where it cannot come into accidental contact with the terminal. You can wrap the cable with electrical tape for added safety.

It is also important to work in a well-ventilated area when dealing with the fuel system. Do not smoke, and ensure there are no sources of heat or open flames in the working area.

Before reconnecting the battery, be sure to clean up your work area and check for any leaks.

Drain the gas tank

To drain the gas tank of a 1999 Jeep Cherokee, you will need to siphon the fuel from the tank as there is no drain plug. This process can be done in several ways, but it is important to exercise caution to prevent static discharge that may cause a fire.

One method is to disconnect the filler hose and vent hose from the side of the tank. Insert a hose, approximately 4 feet long, into the vent tube connection. Insert the hose as far as possible, and cap the end with your thumb. Extract about 2 to 3 feet of the hose, and place the end in a bucket on the ground, ensuring it is lower than the tank. This should start a siphon and drain the tank. If this does not work, you can cut a small slit in the hose, about 3 inches from the end, and insert the tip of a blow gun. Actuate the blow gun in short bursts until the gas starts to flow into the bucket. Depending on your fuel level, you may need several buckets to capture all the fuel.

Another method is to use a cheap siphon hose from Walmart or a similar store. Find a hose that is flexible enough to make the turn in the filler neck. You may need to try a few different hoses to find one that works.

Alternatively, you can use an old electric fuel pump hooked up to a battery. Remove the hose from the filler neck attached to the body and run the hose down. When it is time to switch to another gas can, simply unhook the wire from the battery to stop the flow of fuel.

Finally, if you have a scan tool to activate the fuel pump, you can drain the tank from the fuel rail with a hose into a container. Keep the battery charged while doing this. If you do not have a scan tool, you can run power to the pump or jump the relay with a fused heavy gauge wire. This method will not get all the fuel out, but you can then fill the tank with fresh gas.

Remove the fuel pump

To remove the fuel pump from a 1999 Jeep Cherokee, follow these steps:

Firstly, ensure you disconnect the battery to reduce the chance of a fire. Next, drain the gas tank as much as possible. Siphoning with a hose is not recommended due to safety hazards, so use a siphon pump and a gas can instead.

Now, you need to access the fuel pump. This can be done by either removing the fuel tank or by cutting an access panel in the cargo area. If you decide to remove the tank, be aware that the fuel system is under constant pressure, even with the engine off. Therefore, you must perform a Fuel System Pressure Release Procedure before removing the tank. Once the tank is removed, thoroughly wash and clean the area around the pump module to prevent contaminants from entering the tank.

If you decide to cut an access panel, you will need to lift the carpet in the cargo area and cut a small hole in the metal underneath. This will provide access to the top of the fuel tank, where the fuel pump module is located.

With the fuel pump accessible, the next step is to disconnect the fuel return and pressure lines from the module fittings. Be sure to refer to the appropriate procedures for your vehicle when working with these lines. Once the lines are disconnected, you can remove the plastic fuel pump module locknut and then the module itself. Take care not to damage the surrounding components, especially the fuel tank.

Now that the fuel pump module is removed, you can begin the process of installing the new module. Be sure to follow the manufacturer's instructions and torque specifications for the new module. Once the new module is installed, reconnect the fuel return and pressure lines, and then reinstall the fuel tank if you removed it.

Finally, reconnect the battery and turn the ignition switch to the 'run' position. Listen for the fuel pump to crank up and build pressure, then shut off. Start the engine and check for leaks. If there are no leaks, you have successfully replaced the fuel pump.

Install the new fuel pump

To install the new fuel pump, first, make sure that the new pump looks like the old one. Then, check that the new pump has rubber vibration isolators, one at each end, and any needed adapter sleeve.

Next, place the new pump into the tank, ensuring the rubber 'foot' is in place at the bottom of the pump assembly. Be careful not to damage the float, as this will cause the fuel gauge to misread.

Then, replace the lock ring, ensuring the O-ring is in good condition and seated properly. Reattach the wires, hoses, and fuel lines, and check for dry-rotted hoses and bad clamps, replacing as needed.

Finally, reconnect the battery and turn the ignition switch to the 'run' position. Listen for the fuel pump to crank up, build pressure, and then shut off. Check for leaks, and start the engine, checking for leaks again.

Reattach the fuel lines

Reattaching the fuel lines of your 1999 Jeep Cherokee is a crucial step in the fuel pump replacement process. Here is a detailed guide on how to do it:

Before beginning the reinstallation, it is essential to have cleaned the area around the pump module thoroughly and to have checked for any dry-rotted hoses and bad clamps, replacing them as needed. Zip tie the wire harness and hoses in place, if necessary.

First, hold the O-ring near the tank port area of the pump mount during installation. Be very careful with the pump assembly. Gently install the pump back into the tank, ensuring that the rubber 'foot' remains in place. This 'foot' is located at the bottom of the pump assembly and can fall into the tank if you're not cautious.

Next, while holding the mount in place, reinstall the locking ring. Take care not to twist the O-ring under the lock ring. If desired, apply a small amount of grease to the O-ring to prevent twisting. Ensure that the locking ring is fully clockwise against the stops and properly seated.

Now, reconnect the fuel pump wire harness and hoses. Check again for any dry-rotted hoses and bad clamps, replacing them as required. Zip tie the wire harness and hoses in place, if necessary.

Finally, reconnect the battery and turn the ignition switch to the 'run' position. You should hear the fuel pump crank up, building pressure, and then shut off. Check for leaks. Start the engine and check for leaks again.

Your Jeep Cherokee's fuel lines should now be securely reattached, and your fuel pump replacement process is almost complete. Remember to clean up your workspace and tools after finishing the job.

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