My 1998 pontiac bonneville makes a little grind noise only when I rev it up high so I took the engine cover off and show a little leak by my head gasket and I put my hand on the head gasket cover and every time I heard that noise I felt something hit/vibrate the cover part of the head gasket could that grinding noise come from having a blown head gasket the belt and pulley looks fine we put 134a refrigerant with oil in the a/c to recharge it becuase we thought the bearing didnt have enough oil
What is leaking, oil or coolant. Do you have a blown head gasket, has that been determined? Cover part by the head gasket, what part are you talking about? If it sounds like an internal engine noise, it will still be present when you run it with the belt removed.