: fuel pump suddenly stops

09-08-13, 05:07 PM
I have a 1997 Eldorado touring coupe that the fuel pump has stopped working I have replaced the relay witch did not do anything checked the fuses and could not find any blown fuses. So I replaced the fuel pump with an ac/delco unit and fuel filter and the car started right up and I let it idle for about a half an hour shut the car of let idle again for about 10 mins and shut it off. Then I went to take it for a ride and after about a half a mile and the fuel pump stopped working. I have checked my relay and fuses agian and they seem fine. I was just wondering if any has any suggestions?

09-08-13, 05:21 PM
How about the electrical connector? Check it closely. When the old pump failed it could have caused a high amperage draw and burnt the connections.

09-08-13, 07:30 PM
Thank you ranger, the new fuel pump came with a new wiring harness and connector. Witch was installed. And the old connector seemed to be in good shape. I was just hoping to check everything else before pulling the gas tank again because I am starting to think it was probably not the fuel pump to begin with just something causing the fuel pump not to work.

09-08-13, 08:47 PM
Hard to say, but an easy assumption to make on a 16 year old fuel pump.

Then I went to take it for a ride and after about a half a mile and the fuel pump stopped working.
I assume you checked the fuel pressure to be sure it's the pump?

09-09-13, 12:15 AM
Thanks for the help ranger, no I have not checked the pressure because I can't hear the pump come on and when I sprayed gas gas down the throttle body it started and then just sputtered out.the car has 130.000 miles on it but it has never been driven in the snow and it is always parked in a driveway. I also had quite a bit of work done to it over the course of the last two years. The block has been studded with new head gaskets, chrfab 272 cams, an aj tuned pcm, a higher stall converter, new chrfab valve springs and retainers, and a 3inch catalytic converter and 3 inch pipe going to two flowmaster delta flow 50's muflers, also I just replaced all the rotors and pads with slotted and cross drilled rotors and ceramic pads, and lots of other things too.


Oh, and aj from pcm calibrators is a pleasure to deal with and knows his stuff with northstars.I highly recommend him. And he Is very helpful as I don't know these cars to well yet.

09-09-13, 09:27 AM
Based on what you just said, it sure sounds like a bad fuel pump or FP circuit. I guess you should start by seeing if you have current to the pump, but remember, the PCM only supplies current for 2-3 seconds without cranking, so if you just leave the key on, there will be no current.

Don't hear from AJ very much anymore, but he used to live and work just north of me in Milwaukee Wisc. Used to be a regular poster and he DOES know his way around the Northstar.

09-09-13, 04:26 PM
So by pulling the fuel pump fuse and putting a voltage tester on both ends of where the fuse goes for 2-3 seconds when I turn the key on I should read 11-13 volts from that spot?

09-09-13, 09:28 PM
I'd test it at the fuel pump wiring connector first and work your way back if necessary.

09-10-13, 12:43 AM
Thank you for getting back to me ranger, that's what I was thinking but I was trying to avoid pulling the gas tank just because it pain in the neck and I guess I am a little lazy too.lol. but I am sure with my luck it will be something to with the wiring harnessto the fuel pump.

09-10-13, 09:44 PM
No need to pull the tank to test for current. Just unplug the pump and test for current there (outside the tank).