just completely rebuilt the 3.4 in my 95, and tried to start it, and it will run for about 2 seconds, then shut off, and i can turn the key off, and try it again and it does the same thing. that is as good as it will do. any help on why this may be doing this? i have spark, and i am getting fuel to the rail.

thanks for any help, craig

 

pick up a noid light for injectors and see if when it dies the injectors are firing. the fuel pump relay may be failing. make sure you got all your wiring done up right, then check it again. check crank/cam sensor wiring.

 

I put the noid light on there, and for the couple of seconds it runs, it does pulse.

 

Have you measured the fuel pressure with engine off? It should be 41-47 psi and not drop much over time.

Do you have a lit SES lamp? If so, have you checked for trouble codes?

 

i did turn the key on, and let the fuel pump prime, and then i hit the schrader valve on the fuel rail, and it shot out pretty good, but i do not have a gauge to tell the accurate pressure reading.

 

Pull the vacuum hose off the fuel pressure regulator and see if there is any fuel inside. If there is some, the regulator is defective.

If not, borrow, rent, or buy a gauge. Some auto parts sores will "loan" a gauge out for a full-price deposit The fact that the engine runs at all indicates there is some pressure, but maybe not enough pressure or volume to keep it running.

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i pulled one of the wires from the fuel injector, and put a noid light on it. i can run the car on ether, but when the car first initially starts up the noid light will pulse, for about 2 seconds, but i can keep the car running on ether, but after a couple of seconds, the light will stop pulsing and go out, so something is cutting off the injectors after those couple of seconds. i am keeping 12 volts on all of the injector harness plugs but i know the computer makes the grounds so they can pulse. i have tried 3 different computers, so that is not it. i am really close to getting it running, just some little something cutting those injectors off. i have changed the cam and crank sensors also. hopefully yall can help me out here, surely this has happened to somebody else too. any help is appriciated.

thanks, craig

 

Ok now, that was key information (pun intended). Is the Security lamp on for the two seconds the engine runs? If the anti-theft system does not see the correct key resistance, after two seconds the PCM will shut off the injectors.

Correction, I just tested that and the time is one second.

 

as soon as i turn the key on, the security light comes on, but goes off about 2 seconds after that, before i even start the car.

 

I guess that eliminates that possibility. I am back to suggesting you measure the fuel pressure. Perhaps the injectors stop because the engine stops and not the other way around?

Did you check the SES lamp?