1991 v6 3.1. New Injectors, Fuel pump (bosch replacement). The Car sometimes has a extended crank in the morning, and when hot sometimes it will have a very high idle, 3-4K and slowly come down and starting running on 2-3 cyl's just about to die and sometimes does....

I just checked the Fuel pressure tonite. KOER Its at 43ish PSI and when i rev it, the pressure goes up smooth and gradually to 55 PSI and when i unplug the Fuel Pres. reg. it jumps straight to 55.... After sitting 25-30 Minutes KOEO the pressure rapidly bounces from 5-20psi and settles to about 10. Then we attempt a start, we get an immediate stall, and then a restart and the idle is high and then settles with the about to stall idle with the pressure at and in between 20-55 psi then the pressure slowly calms down to 43ish psi and idles wonderful. Ive got some research to do..... I just wanted to know if anyone has seen this and could pin point the issue.

 

Pull the vacuum hose to the regulator & then watch the regulator port for fuel to come out, it might take a few minutes.

 

Yea ive done that, and Nothing makes it out..... Ive done it while its running, and after i shut it off I never seen gas. left it unhooked for about 10 minutes..... I watched a video in youtube about it taking over 5 minutes for them to show a Liquid leak.... But other than that, i forgot to add, as soon as the engine is off/key off. the Fuel pressure drops to 0psi. Im not sure if these systems are suppose to drop that quick or not.

 

Time to pinch off the return right after the fuel rail, reprime, & watch for pressure to drop. It could be a leak inside the tank, the hose that connects the pump to the fuel line.

 

Oh yuck...... These should hold pressure when the pump primes and shuts off right? hmmm. I guess I'll check that tmrw.... yay Thanks for the input.