the other day i drove to the city and everything was fine untill the car died and i tried turning it over. i thought it was out of gas so i went and put a gallon into the tank and still wont start. i had to have it towed out of the city and has been sitting since. i have fuel at the fuel rail but not too sure if i have a spark. my tach has been dropping to zero fequently so i know the cam sensor is going bad and the crank sensor was replaced a few months ago. any ideas?