Q: Loud tapping under valve cover

asked by on January 27, 2016

I hear a loud tapping noise on the passenger's side of the engine, under the valve cover.

Hello. If the noise is coming from under the valve cover I am certain there is an internal engine problem in the cylinder head. The easiest way to test engine internals is by performing a compression test. However, a compression test wont always unveil the issue. The best way to fully examine internal engine issues is to inspect the internal components such as the camshaft, valve clearances, and rocker arms. Unfortunately, YourMechanic does not provide such service.

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