I have a 5.7 tpi and lately its been having problems starting.

When the motor is cold it starts up without any problems, but as soon as the car is warm and I turn it off and I try starting it back up it cranks but doesn't start.

Any ideas?

Thanks

 

Does it always start when it's cold?

 

Yeah when cold I can turn it off and back on without any problems.

 

Sounds like you might have a bad Ignition Control Module. When the ICM goes bad it usually is worse when hot. The ECM won't pulse the injectors without a voltage signal from the ICM. You can get it tested at most auto part stores.

 

My fuel pump went bad and acted the same way......

 

My mechanic told me it could be the fuel pump as well, I just don't have the money to be replacing things that don't necessarily need to be replaced right now.

I'll go get the ICM checked and I'll write back tomorrow, thanks for the responses.

 

you need to look at fuel press. when it occurs.bad check valve in pump or leaky diaphram in fuel press reg. can cause lose of residual rail press and hard start on hot soak....almost creates a vapor lock condition.but will start perfectly fine when cold.my money is on regulator.remove vac. hose and look for signs of fuel.

 

We are having the exact same problem with our '89 5.7L, we had the fuel pressure regulator replaced and the car ran better but then when it warmed up it would not start. We also changed the distributor cap and rotor.
Also, when running if you rev the engine up and let off it makes an almost backfiring or sputtering sound like the timing is off but that has been checked.
Any help would be greatly appreciated.

 

I've got an 87 IROC with the same problem. After checking fuel pressure, injectors, vacuum, etc., I unhooked the battery for a couple of minutes. Essentially doing a full reset on everything electrical. I know it's weird but it starts now when it's hot. Go figure.

 

If you can, take off the coil, ignition module and get them tested. I brought mine to autozone and they did it for free. If it is your ignition module make sure you get the 369 module. The acdelco # is D1943A the gm # 10482827.

 

Sorry guys I've been really busy.

Ignition module is getting checked out tomorrow, we'll see if that's the problem.

 

Replaced the injectors, and everything is fine now.