Mechanics

NEW FUEL PUMP WON'T WORK

1996 Oldsmobile Aurora

Engine Performance problem
1996 Oldsmobile Aurora V8 Two Wheel Drive Automatic 112000 miles

A week or so ago, my 96 old aurora died on accelerating to the highway, would not restart, 20 minutes later, started, drove to work left running in parking lot for 10 minutes then died again, towed it home, the next day it ran for about 10 minutes then died, could not restart after that, took to auto shop, they said was the fuel pump and wanted $900 to replace, towed back home replaced fuel pump myself for $300, but am still not getting any fuel flow, relay clicks and there is voltage at the plug to the fuel pump which the second new one put in two days, but it won't run, no hum, no fuel to engine, could it be another fuse, switch or relay that I haven't checked, please help... I have read about faulty inertia switches but am not sure.
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Lumpyfish63
August 29, 2010.




If there is power all the way up to the fuel pump connector than the pump must be bad or voltage is low. How much voltage was showing at the fuel pump connector?

Bluelightnin6
Aug 29, 2010.
It's getting about 10.6v, the battery has been really low, i'm having to jump it to get to start, think that could be the problem

Tiny
Lumpyfish63
Aug 29, 2010.
Could be, does it start with a jump?

Bluelightnin6
Aug 29, 2010.
No it doesn't, i've tried 2 new fuel pumps but nothing.
Was just out there, i'm beginning to believe it was never the fuel pump, just something telling the pump not to pump maybe, help

Tiny
Lumpyfish63
Aug 29, 2010.
Are there any other fuses, relays, or switches that i; m not thinking of

Tiny
Lumpyfish63
Aug 29, 2010.
Let's work backwards, the wiring from the fuel pump is a ground and a power. The power wire comes from the fuel pump relay. You said it's good, yes? From there the power comes from the powertrain control module (PCM). Of course there are some fuses to protect the circuit, but you said it has some voltage so the fuses must be good. Since jumping doesn't start it and relay is also good that leads me to believe the PCM might be at fault.
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Bluelightnin6
Aug 29, 2010.
So the pcm would not let the fuel pump run even if it has power? Because at this point i'm beginning to believe that the original fuel pump may not have been bad either.

Does pcm have to be programmed, can I install it myself?

Tiny
Lumpyfish63
Aug 29, 2010.
Really not understanding that, if the pump has power to it than it should run, no way around it. Are you positive that it is getting power? What happens when you provide 12v direct power straight to the pump?

Bluelightnin6
Aug 29, 2010.
Me neither, that was one of the first things I checked, put multi meter on plug leads with key on to check voltage and it was there. Took 1st pump back, got another one, same problem. I'm stumped. Will check voltage again tonite when I get home from work and report results...

Tiny
Lumpyfish63
Aug 30, 2010.
Ok, so the wiring harness has a black/white, a black,
a purple, and a gray wire. I get voltage on the puple wire but not on the gray, any thoughts

thx

Tiny
Lumpyfish63
Aug 31, 2010.

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