Help!!! Motor dies when coming to a stop?

I had a coil start to die on a 360, it would be fine at start up and while driving then about 15-20 mins later or after driving a while on the freeway it would die at low idle. I would have to power brake the hell out of it so it wouldn't die at stoplites. If I went into a store I would have to wait 40 mins for it to cool down so the car would start.