Mechanics

WON'T START

1988 Pontiac Grand Am

1988 Pontiac Grand am, 2.5, 140,000 miles. There is no injector pulse while I am spraying with starting fluid. I have replaced the crank shaft sensor, ecm, pcm, and fuel pump. I still have the same problem. There is a pulse on crank. Can anyone please help with thsi problem?
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Knkracing
May 13, 2006.



Do you have a checvk engine light? Also don't used starting fluid or the engine might end up in pieces.

Explain about an injector pulse. Have you put a noid light on the wire connector to the injector to see if you have a pulse?

Tiny
Losone
May 13, 2006.
There is a check engine light on but no codes in system. I have an initial pulse on crank but after that there is no pulse in the injector. Yes I did put a light on the injector wire.

Tiny
Knkracing
May 13, 2006.
The injector 12v line (gray wire) goes through the oil pressure switch after the fuel pump relay turns on ( 3-8 seconds.) This prevents the engine from ruining if you lose oil pressure. You probably have a bad oil pressure switch

Tiny
Losone
May 13, 2006.
I put a jumper in the oil pressure switch wires and it still did the same thing.
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Tiny
Knkracing
May 13, 2006.
Did you check to see that the fuel pump relay is working? The way it works is it provides power to the fuel pump for 3-8 seconds. By that time engine oil presure is up and the 12V is coupled to the fuel pump. I would like you to check the voltage on the fuel injector gray wires like this.

Put a 12v test light or meter on the injector gray wire. Turn the key on and watch the light it should go on for 3.8 seconds and go off.

Crank the engine, the light should come back on. Try this and let me know the results.

There is a single loose red wire with a green or black terminal in the engine compartment. I want you to try and locate it.

Tiny
Losone
May 13, 2006.
Fuel pump relay is working. Light comes on when cranking, but it goes out as soon as you stop cranking. That is when it stalls. Found the wire but is gray and it does activate the fuel pump.

Tiny
Knkracing
May 13, 2006.

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