My 3.8L SC, 2001 Grand Prix has started to develop a problem. The tachometer sporadically drops to "0" and the TCS comes "on." On occasion, the "check engine" light comes on also. When this happens, there is a slight sputter but the comes continues to run. Upon shutting the engine off and restarting it, the tach and TCS returns to normal. Will this eventually stop my engine and what is wrong with it?