Code P0171, crank no start?

KSULLY1231

MEMBER
2001 CHEVROLET EXPRESS
5.7L
V8
2WD
AUTOMATIC
180,000 MILES

Hi Guys,

My van (Express 3500) has P0171 code; it cranks good but won't start. The fuel pressure readings are 62psi and then drops quickly to 55, then to 30 in about 15 minutes.

I suspected the fuel pressure regulator or fuel pump. So, I replaced the fuel injector/spider assembly with a rebuilt one, also a new FPR. No change in the readings.

I then replaced the fuel pump (aftermarket) and filter. Still no change in the readings and still won't start.

What else could be my issue? Is it possible the fuel pump or FPR is defective?

Also, the front seal is leaking oil pretty badly onto the crankshaft sensor. Is it possible that could be causing the no start condition?

Thank you for your help and assistance.

I'm going to try to figure a way to deadhead the fuel pump to test it.

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
43,393 POSTS

Does the engine run on starting fluid? If so, it sounds like you got a defective fuel pump. Can you turn the key on and see how fast the pump can get to 60 PSI, if slowly the pump is defective, here is information on the code which included a bad fuel pump. Please check out this guide as well:

https://www.2carpros.com/articles/car-not-running-advanced

The P0171 code is a common trouble code that appears in vehicles across various manufacturers, including Chevrolet.

Please go over these guides and get back to us.