Just replaced a fuel pump and fuel filter in a 2003 Denali XL 6.0L., Now I've found that I have no power to the fuel pump. I have tracked the power supply back to the fuel relay and found that the relay is working properly, but I am losing the power supply to the fuel pump somewhere between the fuel relay and the fuel pump. I have looked at the entire wire harness from the relay to the tank and can see no damage what so ever. I beleive that the only electrical connection between the relay and the pump is the one above the tank at the fuel pump and it looks brand new. Any body run into this problem before?

Update on the above question. I originally picked up the replacement pump at the local pep boys and found that they had given me the wrong part. I was working on a 1500 and they gave me a pump for a 2500. Well, while packaging the wrong part back up to return, a small wiring pkg. was not put back in the box and left on my work bench. After returning the part and recieving the correct part and installing it, I found that the fuel pump still did not work. With the tank still lowered, I checked the voltage at the pigtail and found that I did have 12 volts. After scratching my head for a few minutes, I remembered that short wiring pigtail from the first pump that was still sitting on my work bench. I installed it between the fuel pump and the wiring harness and turned the key to the on position, wala! I had fuel !!! Evidently the new pumps are wired differently and need the short pigtail to convert the wire positions to match the new pumps. Funny though that the second pump that I purchased did not have this little pig tail in the box with the fuel pump. Hope this helps anyone else that may run into the same problem!

Thanks I have been having this same problem or it would seem, I replaced the original pump last year and the new one only lasted one month, they replaced it under warranty and that one lasted almost a year, I replaced that one with a different brand about three months ago and it died again. So I am thinking it is some other problem as you described above. The first two were replaced at a garage, you would think they would check the wiring. thanks JAck

I have a question I have a 2003 Yukon Dinali replace the fuel pump pump is not pumping. Nofuel is being delivered up front what is the problem can anyone help me

I just changed the fuel filter and pump on my 03 Tahoe. Then, it wouldn't start. Though frustrated, I chilled for the evening. I had a thought about the factory alarm and kill switch. I had disconnected the battery prior to doing the work, so I thought the kill switch could have been the problem. This morning, I got up and tried to start the truck. I had to toggle the kill switch a couple of times, but then, it started right up! Good luck to those with similar issues.

I don’t have an answer but a question. The yukon, Denali, and the Escalade are pretty much the same vehicle. I to have a problem with replacing the fuel pump. I had to change the wiring pigtail as well. I changed the filter. I have no power to the pump. The gauge is working. Is there an external pump.