Has happened two times, while running the tach drops out to zero, car continued to run the first time and the tach came back on after about 30 seconds, second time the motor stalled out and had trouble starting again. Hasnt seemed to do it again recently but I havent really driven it for about a week or so. Need to change the rad hoses and coolant and all that jazz and after that I think I will take it for spin again. Someone metioned it might be the crank sensor...any opinions? I also just resealed all of the supercharger connections with rtv copper and it seems to be running at a better vac.