I have an '89 that had an intermittent kill issue. It would just stop running whether at idle or running down the road. The only consistent things were that it was somewhere between cold and fully warmed up, and that it would restart once fully cooled down. I read a post here that seemed to match those symptoms and they said replacing the "photo optic sensor" in the distributor did the trick. I found the unit at RockAuto under "ignition control module" and also under "distributor pickup coil", part # LX 122, ($90 approx.). Relatively easy install and it cured the problem 100% !

My thanks to all who post technical info here, as it saved me mucho dollars and time in that case . Because it was temperature sensitive it would have been almost impossible to test the unit as bad. Hope this helps.