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Q: Engine knocking noise, smoke, exhaust smoke

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Yesterday the engine started to knock loudly. There was smoke coming from it. Also the exhaust was making a lot of smoke. What might be causing this?

Hello. There are several possibilities for the engine knock. It could be caused by a busted piston, broken valve, or something internal in the engine. The smoke may be due to an internal damage on the engine block and/or oil leaking somewhere within the system. Have a qualified professional inspect the smoking issue and knocking noise in person in order to have this diagnosed correctly.

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