I have an 89 IROC with 5.0 - have done a complete tune-up. Runs great when cold - start running a little rough when hot - if I re-start the car, it runs good for about 30 seconds and then starts running rough again....any suggestions? Could this be injectors?
thanks

 

Sensors, sensors, sensors.

Namely, idle air control, o2 (because it's the o2 sensor, damn it) MAF, and the like.

 

EGR that was my problem,same symptons

 

I'm not entirely sure how this affects things, but isn't the EGR only active during certain times? I think at WOT and idle, there is no recirculation of the exhaust gases AFAIK.

 

no its active once engine reaches around 120 degrees, under vacuum not wot,when they stick open a bit causes rough idle and drivability problems

 

Hmm, I can see how that would cause problems. OP should check that as well then, definitely.

 

a stuck open egr will make engine sound like it has a radical cam and you wont have much vacuum for brakes. it would also do it all the time, not just when hot. describe the condition of rough. rough idle, rough accel, rough cruise? any smoke or smells? is the idle steady or does it jump around? i need as much info as possible