Good morning everyone. I am at work and cant stay long, but thought I would at least get this out there and see everyones thoughts. I bought this 89 IROC about 2 years ago with a rebuilt engine (# matching) and have driven it about 30k with next to no issues. A couple of times, I had shut it off while hot and it just wouldnt restart. Give it a half hour and it started like nothing was wrong. Last fall, it began to stall every once in a while, but would start back up after a couple of minutes. Finally it shut down in the driveway and would only start if ice cold. If it ran 30 seconds, it would not start back up. Car seemed like it was turning fine, but no fire. I have since went through the entire thing from the tank (minus fuel pump) to the injectors. Most sensors replaced, distributor rebuilt, etc. Found all kinds of bad parts, but none of them fixed it. Finally I tested the injectors and found that 2 were dead and 2 were close! I dont even know how it ran cold. Anyway, I replaced them and the car ran like new....for two weeks. Then it just shut down again. This time, the fuel pump was kicking on when I turned the key. Everyone keeps saying fuel pump, but I hate to go through the work, that I'm not equipped for, if its not that. I keep questioning it because it doesnt always fail. I jumped that "G spot" on the ALDL straight to the battery and it fired right up. Next time that didnt work. This weekend I replaced the battery as it was about shot and put a fuel pump relay on it. No good. However, the next morning it started right up and I have been driving it all weekend. Does anyone have any thoughts. I dont mind the fuel pump answer, but was looking for some descriptions that explained why it would be that when it works sometimes. Also looking for a good 3rd gen guy or anyone that just enjoys pittling on weekends with other camaro guys as funds are short and I'm not sure I can pull the tank alone. Thanks in advance.

Bob
Cincinnati (Fairfield actually)
276-0620

 

The fuel pump is designed to run momentarily when the ignition is turned on to pressurize the fuel system. You need to go to the nearest Murrays, Auto Zone etc... and pick up a fuel pressure gauge. They are like $45. You won't regret it. Next time you have a no start situation, test for fuel pressure, and post results. You want to be sure you're not replacing a good fuel pump for no reason...

 

I actually did go and pick up a fuel guage end of last year when this all started. I had good pressure. Book spec. When this started, I didnt think it was a pump issue because I could hear it pressurize. Its now that the pump quit and to coincide with that, I did not have pressure. Now out of the blue, its working again. Thats why I'm hesitant to believe its a pump. I thought when an electric pump went, it usually went completely.

 

Sounds like you need to verify voltage to the pump next time you have a no start problem. I would believe the pump could be failing and intermittently stop running. Between your fuel pressure gauge and a volt meter, you should be able to determine which it is.

 

Ok, the last time that it wasnt running, right before it started up again, I had done just that. I was actually looking to see if there was a way to run battery power straight to the pump. When I saw that the plug had 3 prongs, I opted to test for power. If the red wire was on the center prong and the black on either side, I got 9volts. I have absolutely no idea what that says for whats happening, but I know its not the 12v that the battery has.