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GMC Fuel Pump Problems

Why is a new GMC fuel pump not working? What are the precautions to be taken when GMC fuel pump replacement is being done? Should GMC fuel pump problems be handled only by a dealer? Finding the answers to these and other questions on GMC fuel pumps is often difficult and time consuming. Obtaining guidance and troubleshooting ideas from Experts is the fast and reliable way to get the required information.

Read below where Experts have answered a variety of questions pertaining to GMC fuel pump problems.

How to activate the newly replaced GMC fuel pump and new relay on a 1990 Sierra 1500 with the ignition in the ON position?

A problem with the connections is the most likely cause for this problem. To identify the fault, turn the ignition ON and test the orange wire at the fuel pump relay plug for power by jumping it to the gray wire. If the fuel pump starts to work, then there may be a break in the green/white wire between the ECM and the relay. If the wire is good, then the ECM could be at fault and will not send out the correct signal to the relay to activate it.

When replacing the GMC fuel pump on a 2001 Yukon XL 1500, what all needs to be removed to remove the fuel tank?

The front of the fuel tank is connected to the charcoal canister by the fuel lines and vent lines. The smaller fitting at the charcoal canister needs to be disconnected by squeezing the line with pliers or by hand. Alternatively, the lines at the front of the tank can be released by squeezing the plastic lock with pliers. Below is a picture.

Releasing the GMC fuel pump

When the straps are removed the rear of the tank will drop down to the ground. When the fuel lines are disconnected, the tank should be slid back and the front will drop. The fuel pump can now be accessed.

How to connect the wires of the GMC fuel pump/sender on a 2003 Yukon?

There should be 4 wires, two black, one gray and one purple, in some cases the colors may differ. The bigger black wire is the pump ground and the other big wire, usually the gray one, is the pump power. The purple wire should be connected to the other black. That will leave one wire at each end that should be connected.

What will prevent a 1994 diesel Yukon 6.5 from starting and no fuel will come out of the bleeder valve on top of the fuel filter after the GMC fuel pump has been replaced?

Keep the accelerator pedal fully pressed while cranking the engine to bleed the system. If this does not work, then it could be that the fuel filter will need to be bled. This can be done by powering up the fuel pump fuse. To do this, locate the small holder in the cover on the right side of the firewall. Remove the fuse and touch the tip to the junction block stud or use a length of wire to make the connection. The pump should now run and bleed any air in the filter,

What is causing the GMC fuel pump to repeated fail and need replaced on a 1997 GMC Yukon?

First, ensure the GMC fuel pump being used is either an AC Delco or Delphi. When the pump is being replaced, if the tank is not cleaned of rust, dirt or debris, it could be getting passed the screen and clogging the new filter. A clogged fuel filter will pump extra strain on the fuel pump, reducing its operational life. When the level of fuel in the tank is below ¼ it causes the pump to run hot and driving regularly in this condition can lead to early pump failure.

A defective GMC fuel pump can affect the performance of the vehicle and even bring it to a standstill. When dealing with GMC fuel pump problems it is advisable for the owner to obtain information on the nature of the problem and the repair alternatives available. The best way to get this information is to contact Experts for their answers and insights.

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