I have a 1990 IROC-Z with a 305 TPI. It was running rough and was hard to start and then replaced the fuel pump and injectors. Now it starts and runs amazing but once it gets to operating temp, it all goes down hill and it runs bad and even stalled at idle. When tested with a noid light, the injectors had a pulse when cold but once it got warm, the pulse turned into more of a constant flutter. Can anyone help shine some light?

So far it has gotten a new:
Fuel Pump
All 8 injectors
Ignition Module
Distributor
PCM

Thank You to anyone who can help! I am just so confused what to do now

 

Have you replaced the fuel pressure regulator?

 

Check the resistance in the coolant temp sensor thats usually the prob with hard and cold starts

 

^^^^^^what he said

 

So Cgus, did this resolved your problem?

 

Does anybody know between which range the temperature of a hot engine is supposed be?

Yeasterday, I cranked it up completely cold (5000ohms), let it run for 5 minutes and it reads 700 ohms whould correspond to about 60C or 140F. Is it normal?

 

For a 5 minute warmup, 140 degrees is probably normal. If the motor has not been modified, it should have a 195 degree thermostat. Given sufficient time to warm up, the coolant normally gets to about 200 degrees.

 

Ok, thank you