I guess you could call it knocking I could hear it in the cab with the radio and a/c on. it would also do it in neutral. The car has 180,000 miles on it. I just got the thing for free from my mother in law all it needed was a clutch master cylinder and a battery. it probably sat without running for about 4 months. It almost acts like the motor has seized up. I checked the oil all looked good. not sure about fuel or spark. I need to pull the valve cover and timing cover to check the belt and valves.