2000 Impala 3.8 110k no fuel pressure

cw41

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#16
Its dropped slowly down to about 38psi in about 3 hours.
 

The old man

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#17
I was just wondering if it starts and stays running now?
 

cw41

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#18
it does start but not well, stumbles and can smell rich exhaust. Engine runs rough. fuel pressure has not dropped below 35psi yet.
 

cw41

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#20
I believe my shop book says 50-52psi and when it ran rough my gauge showed 50psi. Could I possibly have a bad crank or cam position sensor? No codes other than the p0001 relating back to the pressure regulator which is new. thanks again
 

billr

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#21
If fuel pressure is 45, and should be 50-52, why wonder about anything besides fuel pressure for now? Find out why that is low, fix it, and see how it runs after that...
 

kev2

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#23
try a fuel filter ?

At the parts store ask about a loaner fuel pressure gauge to DBL check.
 

cw41

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#24
It was new about 5k ago, sock on old pump was clean and looked into tank with flashlight and no debris.
 

kev2

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#25
frame mounted filter is new OR the sock is new... hoping the frame filter would help get the PSI up, otherwise the pump is suspect-
 

cw41

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#26
The main problem now is I have to jump the b1 and a3 to power the fuel pump. Thats the only way I was able to develop the 45psi. It developed the pressure immediatly with the jumper. Without the jumper and fuel relay reinstalled, I can turn the key on, pump runs for about 2 seconds and stops and no power to it while cranking. I can do this several times and the pump runs for 2 seconds and stops. I thought the cranking energized the a3 pin?? I don't know but it seems I have a bad ground or I just don't know right now. Any more ideas are appreciated.
 

The old man

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#27
Here is good reading from my car program that tell you how the system works when it comes to fuel and ignition as far as starting and energizing the fuel pump relay. I can not get a good copy of the schematic of the system on my printer from this program, but I will look at another program and post it if I can.
 

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The old man

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#29
Have you check with a voltmeter at the PCM port#3 for voltage when you are cranking it? Don't know what the exact voltage will be, probably 12 volts. If there is voltage then you have wire problems to the relay.

Did you look around on the Ignition control module for bad ground, broken wires, corrosion etc.?

Just throwing things out. Will it still start now , but running rough, or not at all now.
 

cw41

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#30
I didn't check with a voltmeter. I did look around the ing module and all looks good. The coil pack has a ground wire and it is good. It will hardly start, runs very rough and rich.