overheating and grey smoke out of tail pipe and hard to start all of a sudden. on 2000 Volkswagen Jetta

it is overheating and grey smoke coming out of tail pipe.

Asked by for the 2000 Volkswagen Jetta
Grey smoke/White smoke is often times the head gasket (coolant getting into the cylinders). Blue smoke is oftentimes OIL blowing past the rings and getting burned up.