Please help fuel pressure issues

[Bishop405]

Hello all, I’m new to my ls v8 and having some issues. I have not been able to get fuel pressure to the fuel rail at all. I’ve replaced the fuel rail pressure sensor, fuel pump twice, jet pump and fuel filter. I’ve verified fuses & no clogged lines all the way to the fuel rails. I’ve hooked into the computer with Forscan and the only codes are abs related really scratching my head here. The car thought it was being stolen and I’ve gone threw the pats system to fix that already. Anything helps

 

[joegr]

Okay, I don't understand. Surely you tested for power at the fuel pump before replacing it. If you have power at the pump, then it should be running. If you don't have power at the pump, then why on earth would you replace it?

What is it? Power or no power?

 

[Bishop405]

Yes it has power, it primes the pump but that’s it. I have verified that it does have power. It just doesn’t build pressure at the fuel rail. I am thinking it is not receiving a rpm signal.

 

[Bishop405]

I bought the car not running and someone had tore the fuel pump out and left it out. I’ve cleaned the tank to the injectors. They said it drove to work parked it and wouldn’t restart

 

[joegr]

... I am thinking it is not receiving a rpm signal.

There isn't one.
The REM controls the fuel pump by PWMing the negative power lead to the pump. It determines how hard to drive the pump via command from the PCM. The PCM reads the fuel pressure sensor on the rail. Even with some failure of the pressure sensor or between the PCM and the REM, you would get enough fuel pressure to at least start. It sounds like you have a mechanical problem. Blockage in the fuel line, incorrectly connected jet pump, bad jet pump, clogged fuel filter (behind the front left wheel liner), ...

 

[Bishop405]

I will double check again, but I have verified it flow air from tank to fuel rail