my 90 ls has been giving me some problems it will run fine when i first start it in the morning but when i stop and shut it off when im done driving and go to start it back up it will idle real rough and then shut off after i do this a couple of times and give it some gas it runs fine i was thinking it was the timing but i checked it and its right on the red mark anyone know wat the problem could be?

 

Main Relay?

 

Do you have any problems after the engine fully warms up but before you stop the car?

 

Sounds like you have a fuel pressure issue to me. Can you give a little more detail like how long you drive engine temp, how long it sits, if you start the car and let it run rough will it die or dose it smooth itself out

 

anytime after it warms up, the temp is normal, right after i shut it off it does it but if i let it cool down it will start up fine, when it runs rough it will die unless i give it gas or put it in gear

 

no it runs fine after i get it started just when i go to restart it

 

You're probably looking at either a clogged filter or an ignition problem when the car heats up. Try checking the spark at all four wires and either check or change the air and fuel filters. If the ignition doesn't check out, have the ICM and coil tested at a parts store.