91 Lumina 3.4 No Go AGain Ugh

[comet240]

ok a week ago i replaced the crank shaft sensor in the oil pan been driving fine a week now i was making a trip to Toronto today which is a couple hour drive i was pulling into my friends driveway thats not far from me after driving myself around shopping for a couple hours the car just shut down i tried restarting it but it seemed to wanna fire for like a moment then it wouldnt just turns over
what sensor would it most likey be now? after this i selling it cuz this 3.4 engine is killing me

[richtazz]

I would check the wiring between the CKPS and the ICM first. IF that checks out (no cuts, corrosion, rubbed spots, etc....), then I'd suspect a bad ECM, especially if it's the original one, and has the service number 1227727 on it. That number was pretty failure prone due to water intrusion issues.

[comet240]

hi sorry for the delay i just got back from my holidays

umm what is the CKPS and the ICM?? how can u test the ECM?

and well i tested the fuel system i put a fuel pressure gauge on the rail and i turn the key to on it goes up to 60psi but then drops down to 0 i read in my book can be a regulator or pinched lines etc or even a leaking injector

basiclly i know i can replace the regulator easliy but how the heck do you know ur injector is leaking or how to test for it?

[comet240]

hi i did more testing

like i said earlier if i just turn on the key the pressure goes up to 60 then to 0

now i tried starting it it has done couple things

one when starting it goes to 35 psi when i stop turning it goes to 40 and drops to 0
or it has done
when starting it goes to 35 when i stop goes to 60psi then pauses and drops to 40 psi and is holding for a bit
or it just does when starting it goes to 35psi and then when i stop ot goes to 40 psi and holds

i checked if i get a spark and i do get one, so is it not getting gas or is it the computer or what not? and still what are those other abbrivations u said

[comet240]

hi i tried some more testing if i spray starter fluid in the intake it wont start

now i tried taking the front spark plugs right out and i prime the pump turning key on and letting it goe to 60psi then it drops to like 10psi and holds now i noticed that the middle cylinder is filling with gas only its full of gas and the other 2 didnt is that now the regulator problem or a sensor problem?

[richtazz]

Just for reference to answer your question:

CKPS (CranKshaft Position Sensor)
ICM (Ignition Control Module)

It sounds like your fuel pressure bleed off is from the injector in the middle cylinder you're saying is filling with gas.