1998 Dodge Intrepid Engine Dies at random

I have a 1998 Dodge Intrepid that dies every so often. The engine was replaced about 5 years ago because of smoking due possibly to leaking valve stem seals. It was a long block replacement. Last year this symtom occured mainly during the summer months were I would be driving along ok and then the engine woud just shut off. Meaning the Tach would go to zero for no apparent reason. I would pull over and after a few tries it would start as if nothing happened. It seemed that the hotter the ambient tempeture the longer I had to wait before it would restart ( sometimes up to 20 mins. ). I finally descovered that one of my twin cooling fans was not working at all and I had a pretty big coolant leak. Thinking that was at least part if not all of the problem I replaced both the radator and coolant fan assemblies and the dying problem seemed to go away until earlier this year when it happened a couple of times in the late winter/ early spring time frame. Although both times I was able to restart the car right away. But about 3 weeks ago it happened again and it took at least 45 minutes of siting before it would restart and then I was able to drive it maybe half-a-mile before it died again. When the wrecker finally dropped the car off in front of my house later that evening I was able to turn the key, start the car, and drive it up the driveway with no apparent problem. Note: When the car died that day the temp. Gauge was indicating normal and as I was trying to restart the car I could hear the fuel pump spin-up normally. My gut feel is that the coils are all at once being told to stop firing when this happens and if that seems to be true then do I need to look at replacing the Powertrain Control Module (PCM) or do these symtoms point to a problem somewhere else?