930 Turbo Engine Quitting

We have a 1987 930 Turbo. After maybe an hour of driving, the engine will sporadically just quit, and then it won't re-start. It will start only after waiting an hour or two, kind of like something needs to cool down. This makes the car almost unusable. Please help.

I am no expert but it might be some sensor. A car would normally reach the regular temperature within several minutes, not an hour, so that kind of kills some of my theories lol. Rennlist forums would be your best bet to get the answer online.
Good luck.