Tapping sound from engine

Maybe from lack of oil changes or over rev of engine.
Go to the auto parts store and buy good oil and filter and get a can of Marvel Mystery Oil (red can) and make sure the engine is 1 quart low on oil. Pour the Marvel in with your oil and let the engine idle for up to 2 hours.Then do an oil and filter change. The Marvel is a heavy detergent that will clean up your engine and wash most of the dirt into your old oil filter.Be nice to your engine!