Why would a 1991 Buick Park Ave stall while you are driving it down the highway and then it won't start again for a while?

I have a '92 PA that would die after it warms up. I had to have the crank sensor replaced and later had the cam sensor replaced. Either of these sensors can cause this problem. The computer needs both of these signals to send the fire signal to the correct spark plug. The old distributor used to do this function. Having the error code read out will tell you if this is the problem.