i had a 91 beretta w/ 3.1 that had a similar problem. i had the same symptoms once on a trip home. when i came to stops i stayed on the gas and used more brakes. i parked it to work on it the next day. when i went to work on it it ran fine. so i drove it. i parked it for about 10 mins (like yours) and it did the same thing again. this time it started running real bad on the trip home. it was missing on most of the cylinders shooting flames out the pipes and everything. i live 30 miles from nowhere so i just stayed on it hard all the way home. i checked coils and all that was fine except the timing was off (way off). so i had to replace the timing chain. along with that i replaced the cps. that fixed the timing issuses that i probably caused. it ran fine for a couple of days and started acting up again. a friend of mine who had a few of these motors told me to check my injectors. sure enough 2 of them had gone out. put in new injectors and it ran like a charm. hopefully something in this long story can help you out. good luck
