Okay not sure what to do about this. My blazer seems to have issues if the outside temp is above 95. WhenI come to a stop after about 30 secs it will surge and immediately die. It will always start back up but as soon as the next red light it dies again, but only does it when its very hot outside. Its an 89, 4.3 liter, auto, 4wd, other than this one issue and the ac being out it runs great....any thoughts?

 

I`m taking a wild guess at the ingition module heating up and shutting down..but thats only a guess, theres a way of testing that part they used to do it in auto school with a heat gun..I dont quite rem it..

 

I would have posted sooner, but forum problems are prohibiting me from posting in most cases.

Anyway, an '89 does not have an ICM in the sense of the newer trucks. It is a solid state unit in the bottom of the distributor.

The fact that it surges then dies would lead me to believe that there is some kind of either fuel supply problem or vacuum leak. The fact that it only does it when it is very hot outside is a bit baffling though unless it is a problem of fuel vaporizing in the throttle body.

Does it do this more when the engine is fully warmed up or does it not matter?