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Well I lent my mom borrow my car to go to the store and I got a call from her saying that my car wasn't going and she heard a loud pop and that she popped the hood and the spark plug cable was off but when she unplugged it the whole spark plug was on it I check if it got stripped and it want it threaded all the way in and ran fine for a whole till I shut it off anyone can help me on why did this happen?