Little Bear

After getting burned with aftermarket parts I only go with AC Delco.
And I think my problem was the same, get warmed up and quit, sit on the side of the road till it cooled and it would start right up

Joe Winsor

Hello again. I ordered a new AC Delco distributor from rock auto. Got it installed this morning. Fired right up. Ran great for about 5 minutes and died. Restarted briefly two times and now will NOT start.
Hooked timing light up to #1 wire see if there is spark and YES there is. Seems a little weak, but it's only cranking.
There is NO fuel spray at TBI, but I do hear fuel pump run in the tank. Before I troubleshoot, I was looking for anyone's thoughts?
thanks
Joe

oilcanhenry

No fuel spray, then something is amiss. In such an old vehicle perhaps it is the fuel pump (I am assuming you ditched your fuel filter here) so it's probable that your ICM is a piece of junk (common with junk built in Asia) and is not allowing your injectors to operate or there is no fuel being delivered to them for some reason. Has the fuel pump ever been replaced that you know of? Have you checked the fuel pressure?

PNW NBS Z71

If you have fuel at the throttle body, crack a line to see, then like @oilcanhenry says, there is a pulse signal problem. That can be from a faulty pickup coil in the new/reman distributor or the ICM. This back and forth crap sucks.

Joe Winsor

I replaced the distributor with a new rebuilt AC Delco from rock auto. Started up fine, ran a few minutes and died.
I hear pump in tank run, it starts normal with injectors spraying. Engine dies after a minute almost exactly. Upon immediate restart attempt, it has light on timing light blinking, but NO injector spray. If I wait 10 to 15 mins or so and try to restart, it will, but dies after almost exactly after one minute. Seems to be a cycle.
Is it possible that when the key is first turned on and cycles the fuel pump on, that pushes enough fuel to run for 60 secs, but then the fuel pump might have something mechanically wrong that it stops pumping? Or do you still believe it's something between the distributor and the ECM?
Just seems bizarre that it will run normal for 60 secs and then die.

Any thoughts on what could be going on now?

PNW NBS Z71

You need to get a fuel pressure gauge on this and monitor what it does when the problem occurs. I feel that if you have a good distributor assembly, you likely do, then the fuel pressure is a problem but a mechanical gauge is needed to monitor. I am a firm believer in basics first and based off of your initial description of the problem it sounded like the distributor was the cause but a fuel pressure test is also something I would have checked in the beginning. Basics state you must have fuel, spark and compression for the engine to run.

Rednucleus

No way it would run more than a few seconds on initial pump prime only. Next time it dies, try pouring fuel down throttle body to keep it running. If it runs you know your spark is good so can concentrate on fuel side of equation. Have you checked fuel pressure; how old is pump? I believe you can use a light to verify that injectors are firing. My 93 has had same symptoms with a bad ICM - I know you have tried more than one; maybe something in the wiring?? When it dies does it shut off quick like turning off key or slower like starving for fuel?

Joe Winsor

when it dies, it just shuts off. I watched the injectors spray just fine up to the point it shuts off. Then will not restart. I don't have the inline fuel gauge adapter. Tomorrow Im going to investigate both the Fuel Pump Relay and Fuel Pump Oil Pressure Switch.

PNW NBS Z71

I don't think I have ever seen where a failing fuel pump will be fine for about 1 minute and then shut down. I am leaning toward another problem.

Rednucleus

After it dies, when you cycle the key to restart do you hear the fuel pump prime again?