GM Repair Problems? Ask GM Repair Expert Now.
Hello, my name is***** usually means the fuel tank transfer pump has failed but could also mean a problem with sender or cluster. I'd start by checking diagnostic codes if possible because that will usually point toward problem. Otherwise Monitor the scanner for the fuel level sensor values. An empty tank should have about 2.3 - 2.5 volts while a full tank will read 0.5 - 0.7 volts. If the sensors do not read correctly ohm check the individual senders. Values of 40 ohms full to 250 ohms empty. If the sensors read correct, use the scanner to command the fuel pump relay on. Verify battery voltage and a good ground to the transfer pump in the rear of the vehicle. If the power and ground supplies are good, replace the transfer pump. Let me know if you have more questions or if there is anything else I can do to help. Thanks.