Replacing The Fuel Pump In Your Commodore Ute

Replacing the fuel pump in a Holden Commodore Ute can be a challenging task, and the process may vary depending on the model year and specific configuration of your vehicle. Here's an overview of the steps involved in replacing the fuel pump in a VS Commodore Ute:

Firstly, it is important to confirm that the fuel pump has indeed failed. This can be done by checking for the absence of a 'buzz' from the rear of the car when the ignition is turned on or by checking for fuel pressure at the fuel rail. It is also recommended to check for any electrical issues, such as a blown fuse or faulty relay, as these are easier and cheaper to replace than the pump itself.

Once it is confirmed that the fuel pump needs to be replaced, the next step is to drain the fuel tank and remove it from the vehicle. This process can vary depending on whether the Commodore has a live axle or independent rear suspension. For live axle models, removing the Panhard Rod can make the task easier. In any case, it is important to work in a well-ventilated area and take precautions to avoid accidents, as fuel can be highly flammable.

With the fuel tank removed, the next step is to disconnect the fuel lines and electrical connectors from the pump assembly. The pump sits inside a swirl pot within the tank, which can make it tricky to manoeuvre. The pump assembly will need to be rotated and carefully removed, being mindful not to damage the fuel gauge sender or the float attached to it.

When installing the new pump, it is important to follow the correct procedure and ensure that all connections are secure before refitting the fuel tank. It is also a good idea to start the engine and check for any leaks or issues before refilling the fuel tank completely.

Removing the ute floor

Prepare the Vehicle:

• Park the vehicle on a level surface and engage the parking brake.
• Disconnect the negative terminal of the battery to prevent any accidental electrical shorts.
• Gather the necessary tools and safety equipment, including gloves, eye protection, and a jack.

Remove the Ute Floor:

• Locate the ute floor behind the cabin.
• Using a suitable tool, carefully remove the Phillips screws around the edge of the ute floor.
• The ute floor may be sealed with seam sealer, so be prepared to use a pry bar or similar tool to gently lift and separate it from the floor.

Access the Fuel Tank:

• With the ute floor removed, you will now have access to the fuel tank.
• From behind the driver's seat, locate and remove the screwed-on hatch that provides access to the fuel pipes and wiring.
• Disconnect the wiring and fuel pipes leading to the tank. This may result in some fuel spillage, so have rags or a suitable container ready to catch any fuel.

Remove the Fuel Pump:

• Return to the rear tray of the vehicle and locate the ring of screws securing the fuel pump and gauge sender assembly.
• Carefully remove the screws, being mindful not to damage the gauge sender float to ensure your fuel gauge continues to function properly.
• With the screws removed, carefully lift out the fuel pump and gauge sender assembly.

Remember to work carefully and methodically throughout the process, especially when dealing with fuel lines and electrical connections. Always replace components in the same way they were removed, and ensure that everything is securely connected before reinstalling the ute floor and screwed-on hatch.

Accessing the fuel tank

To access the fuel tank, you will need to remove the ute floor from behind the cabin. This involves removing numerous Phillips screws around the edge. You may also need to lever the floor up as seam sealer may be sticking it to the floor. Once the ute floor is removed, you will have access to the tank.

From behind the driver's seat, there is a screwed-on hatch that needs to be removed to access the fuel pipes leading to the tank. There should be two sets of wires: one set for the pump power and another for the fuel gauge sender. Disconnect all of these wires, being careful of any spilling fuel.

At this point, you should have enough room to undo a ring of screws to remove the pump/gauge sender assembly. Be careful not to damage the gauge sender float, or your fuel gauge may not work properly.

If you have a live axle Commodore, removing the Panhard Rod will make it easier to get the pump out. You can do this by marking which end is which, then removing the bolt and nut from the bracket on the body and removing the nut and retainer from the diff end.

Now, you can start the process of removing the fuel pump assembly from the swirl pot. This can be a tricky manoeuvre, and you will need to rotate the assembly to get it out of the tank. Be careful not to bend the rod that the fuel gauge float is attached to.

Disconnecting the fuel pipes

First, you will need to remove the bottom two 7mm bolts. Be careful not to get fuel on yourself as you do this. Then, remove the gauge electrical connector and the two fuel lines. To do this, undo the clamp and then twist the hose from side to side until it loosens, then pull it back off the outlet.

Next, you will need to remove the remaining five bolts (7mm). Getting the assembly out of the swirl pot takes some manoeuvring, and on VR-onwards models, there is a return hose that runs from the swirl pot to the return outlet that needs to be disconnected before the assembly can be removed from the tank. This return hose should be secured so that it protrudes from the tank opening and can be reconnected later.

Now, you will need to slide the assembly in until you have about an inch or two showing, being careful not to bend the float rod or dislodge the filter screen. Then, rotate the assembly until it is in the correct orientation (outlets and terminals facing the right way) and push it in.

Removing the pump/gauge sender assembly

To remove the pump/gauge sender assembly, you will need to first remove the ute floor from behind the cabin. There are many Phillips screws around the edge that need to be removed. The floor will also have seam sealer sticking it to the floor, so it will require some levering to lift it up.

Next, from behind the driver's seat, there is a screwed-on hatch that needs to be removed to access the fuel pipes leading to the tank. There should be a set of wires – one set for the pump power and another for the fuel gauge sender. Disconnect all of these, being careful of any spilling fuel.

Now, from back in the tray, you should have enough room to undo a ring of screws to remove the pump/gauge sender assembly. Take care not to damage the gauge sender float, or your fuel gauge may not work properly.

Finally, take care to replace everything as it was removed. If anything is put back on the wrong way, it won't work.

Refitting the new pump

Once you have removed the old fuel pump, you can start the process of refitting the new one.

First, you will need to prepare the new pump. This involves attaching the rubber insulator to the bottom of the pump, as well as the filter screen and the cork gasket. You will also need to connect the electrical connector and push the outlet coupling up and away from the pump body.

Next, you can begin the process of fitting the new pump assembly back into the tank. This can be tricky, and you may need to manoeuvre the assembly carefully to get it into the correct position. The pump end should be slid in first, followed by the rotation of the assembly until the outlets and terminals are facing the right way.

Once the assembly is in the correct position, you can line up the gasket and fit the mounting bolts. You can then attach the fuel lines, with the supply line connecting to the top outlet and the return line to the bottom one. The electrical connectors can also be attached at this point.

Finally, you can add some fuel and check that the pump is functioning correctly and that there are no leaks. It is a good idea to go over the mounting bolts again to ensure they are evenly tightened.

And that's it! You have now successfully replaced the fuel pump in your VS Commodore Ute.

Frequently asked questions