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2000 Pontiac Firebird, 3800 auto
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Discussion Starter · #1 · (Edited)
So, I've been having a weird intermittent issue with my car. In short what is going on is I have been having an issue where the fuel pump will not fire after shutting down the car while it's warm after a reasonable amount of driving, and it will not restart until it cools down. I replaced the following parts: Crank sensor, cam sensor, fuel pump relay and fuse and the fuel pump and filter were changed by the previous owner before I bought the car (which was March this year, those parts were replaced a couple weeks before I bought the car). The parts I personally replaced were all with ACDelco parts. No trouble codes as well, which baffles me to a lesser extent. I'm at a loss as to what could be going on here, so that's why I'm giving here a shot in asking what's going on here. If anyone has any questions or wants more information let me know and I will answer everything to the best of my abilities. Thank you and I apologize if this is the wrong forum.
 

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I recall this being an occasional issue for some folks, and hopefully others chime in with their success stories.

It sounds like a security/passkey or similar issue, which will stop things in their tracks, before any of the engine components are involved. There may also be something wrong with the fuel components installed, and you may want to doublecheck the wiring for pinching or grounding issues, too. Not sure how comfortable you are going around the car with a multimeter, but that will be a big help in tracking where the signal stops. Also, a fuel pressure gauge will give you some additional info while figuring it out (tool type borrowed from store, or add-on part that sits on rail for parked checks).

Good luck, and let us know what you find. If you can't figure it out, just sell that nice car to me and I'll just turn it into a racecar with no concerns for factory wiring. :LOL:
 

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2000 Pontiac Firebird, 3800 auto
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Discussion Starter · #3 ·
I recall this being an occasional issue for some folks, and hopefully others chime in with their success stories.

It sounds like a security/passkey or similar issue, which will stop things in their tracks, before any of the engine components are involved. There may also be something wrong with the fuel components installed, and you may want to doublecheck the wiring for pinching or grounding issues, too. Not sure how comfortable you are going around the car with a multimeter, but that will be a big help in tracking where the signal stops. Also, a fuel pressure gauge will give you some additional info while figuring it out (tool type borrowed from store, or add-on part that sits on rail for parked checks).

Good luck, and let us know what you find. If you can't figure it out, just sell that nice car to me and I'll just turn it into a racecar with no concerns for factory wiring. :LOL:
Thanks for the well wishes! I'm beginning to think its something to do with the fuel pump although going around with a meter and checking grounds and wiring isn't a bad idea at all. I did do a fuel pressure check and everything checked out as far as that goes. I'll certainly report back if I solve that issue but after personally narrowing down things I believe the pump is suspect, which according to the part numbers on the work order is a off the shelf O'Riley pump. It's strange though that it would do this after a few months of virtually trouble free driving.
 

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2000 Pontiac Firebird, 3800 auto
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Discussion Starter · #4 ·
Okay, so I'm here to report back on what's going on. Everything seemed fine when I probed around with a multi meter, and too I did check my grounds. I started the car this morning for a short drive and noticed it was a little slow to start up, but ran fine. The pump did not give me any problems, although too I was not driving it all that much. I did a bit of looking around and found the slow start could be because of the Fuel Pressure Regulator.
 

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Couple things:

Intermittent/Latent failures don't magically solve themselves. There's still possibly an issue somewhere that you haven't touched, unless new components directly impact the exact change you're monitoring. (don't recall if you said you swapped out the potentially store-brand pump, etc.)

Fuel pressure regulators don't fail often, and you already said pressure on the rail "checked out" when you put a meter on it. That's not randomly going to change a few days later just because you're still hunting for another issue. If the pump is able to build the pressure and maintain it under all conditions, and the regulator maintains it at a steady level (with vacuum reference that increases pressure a bit under load/accel), the fuel system to that point isn't a main issue.

Unrelated, the word "too" has some rules of use, so that dropping it in the middle of a sentence doesn't kill reading momentum.
 

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If this is a security/passkey issue then the car would restart after 10 minutes from the last key cycle. My wife's Grand Am would do this. I searched various forums and found that other GM cars had the same issue, but these were also models that had the ignition switch in the dash vs the steering column. Many people had the switch replaced, but I suspect that they didn't have the lock cylinder replaced (which involves rekeying the lock). My theory is that the play in the lock cylinder housing and the lock cylinder itself would increase over time causing a resistance issue. I recoded the lock cylinder when I replaced my switch and never had another starting problem. If your car will restart after sitting for 10 minutes or longer then I'd look at the ignition switch.
 
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