So i've been having an on going problem that i cant figure out. Its a 89 tpi 305. After i drive for about 20-30 mins when i get the stop lights the idle starts to drop not misfire just idle lower and lower each time i stop till it will just die out. If i restart it right away it will idle low for a few seconds and die, but if i turn the key back and shut everything off and restart it, It will run fine for another 20 mins. I have no idea what to even look for, im hoping someone has had this prob before

 

I would check ignition timing and also make sure that there is no coking on the throttle body, clean it with some throttle body/carb cleaner. What are the condition of your spark plugs, what is your fuel pressure? Check the normal stuff and get back to us.

 

timing is fine, tb is clean, plugs newer and fuel pressure is at 50 but never got a chance to check while it was happening. I think its something electrical because when i power everything down its fine for awhile

 

You might want to check your TPS (throttle position sensor) voltage at idle. The details are in the FAQs. Also, the IAC if the TPS looks good. Those two components control your idle.

 

I checked both numerous times