got a problem with my golf gti 8v it wont tick over when running. it will run if you start in on the key with your foot on the gas peddle but wont if you dont, and as soon as you lift off it cuts out. Its popping and banging when driving as its missing, its got no pull what so ever. if they engine stalls it wont bump start will only start on key. Im thinking that either the mafs gone or theres a problem with the crank sensor. Has anyone else got any suggestions on whats amatter with it?