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Q: Engine knocks

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The engine knocks on my vehicle.

A: Engines can make a lot of different noises ...

Engines can make a lot of different noises when there is something wrong. If it is extremely loud and consistent, your engine will need replaced. If it is ‘knocking” when the engine is cold and is quiet when it’s warm, it could be “piston slap”. This is worn cylinder bores and piston skirts. If the noise is only when the engine is hot, it could be “pinging”. Also known as pre-combustion, or detonation. This happens when the engine is overheating.

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