2001 Pontiac Aztek

While im driving the car seems to stall the radio stops and the engine lights in the dash flicker. It takes about a half second the car doesnt seem to lose any power and I dont have to restart the engine. In the manuel it talks about the car switching over to two 2 cylinders when it over heats. Thought this was it at first but im not over heating. Also it doesnt do this every time I drive seems like every other time. Another way to describe it is the car seems to restart while im driving