91 3.1 keep stopping....Help please
 

I have a 1991 V6 3.1 RS Camaro. It starts and runs fine but after about 5/6 miles it just dies, it is just like the key has been turned off. When it has stopped there is no spark. the engine has not over heated and the fuel pump seems to be working fine. I think that some thing in the ignition system is getting to hot and then failling, when it cools it works again. But what? I have fitted a new coil and new ignition module but still no fix. Any advice will be most welcome. thank for reading.........Chris