View Full Version : fuel problems


Afterfx
Dec 13th, 04, 11:48 PM
I have a 94 camaro that I jsut replaced the fuel pump in because the old one went bad. Now, when I turn the key forward, before I start the engine, instead of the fuel pump priming for 2 secs and then stopping it continualy runs. Then when I start the car it revs to 3000 rpms and then dies, even if I push on the gas pedal. It's like the fuel pump shuts off. After the car dies the pump turns back on a couple of secs later. Anyone got any ideas? I have also replaced the filter and fuel pump relay. I had heard it's an electrical problem, but the only other thing I could think of was the computer (ECM) might be bad.

Everett#2390
Dec 14th, 04, 01:55 AM
Go back over the areas you worked in, you may have pulled a wire off or forgot to attach. If it hasn't been started a few times, there may be a chance of air still in the fuel lines and they are not purged of airlocks yet.

Either cycle the pump on/off a few times, or remove the fuel pump relay and short with a fused jumper across the power leads to energize the pump and allow it runs for a couple of minutes. Then, replace the relay and attempt to start normally.

After the above suggestion, I'd disconnect the battery for 5 minutes, and start over.

If it still doesn't act the like it should, then beg/borrow/steal/rent a scan tool and see what codes there are.

Oh......Welcome to the Club! Lots of good expertise here.......I'm still learning.

Afterfx
Dec 15th, 04, 06:20 PM
Okay! Couldn't be fuel pump regulator. Regulator only controls fuel pressure not pump activation. If that was the case, if a car was in an accident and the fuel lines were busted and the regulator controlled the pump you would never build pressure and fuel would spray every where. That is a safety procedure put in by GM. It has to be electrical. I know its not the fuel pump. I check the voltage running to the connector where the fuel pump plugs in and it has 12V running continuosly. When priming the pump it should power on for about 2 sec then stop. It should only have continuous power when the car is running. with that said the pump doesn't have a short in it. I have now replaced the ECM and it still doesn't work. I am going to try the ignition switch and module. From what I understand the ignition grounds the pump relay to make it start pumping and I think it may be shorting out. I also don't know the conditions of the car before the pump went out. I just bought it with the pump out from a friend and she doesn't know squat about cars.