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Q: tapping from under the hood, faint exhaust smell, poor performance

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I have an issue with a taping sound coming from under my hood. it is hard to locate while looking but however I do smell a faint gas smell as well as what seems like poor performance. I am not sure what it could be, but I have read that it may be an exhaust manifold gasket leak or the whole manifold. I would like to have an idea of what it is before I have someone replace something and not fix the issue.

My car has 133000 miles.
My car has an automatic transmission.

Hello, thank you for writing in. Typically a tapping sound from the engine is a valve issue. This would also help explain why you may be smelling gas or exhaust build up. When intake or exhaust valves are not functioning, excess fuel may be pumping into the system, or exhaust fumes may not be getting completely sucked out of the engine. Your attention should be on testing and diagnosing a potential valve issue first. Due to how complicated the valves really are, and the fact that there may be an underlying cause to the what is happening with the valves, it is recommended you seek professional help with these issues. If you would like to schedule an appointment with our technicians, contact our service department.

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