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Q: Engine knocks, tailpipe blows white smoke

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When I turn the engine on, the tailpipe blows white smoke out. The car is also shuddering. After I turn the engine off, it starts making a knocking noise. Is my engine going out or is it something else causing this?

Hello. There are a few things that can cause this. If the smoke is white then you may have a blown head gasket. This is a common failure on this vehicle, especially if it has ever overheated. If the smoke has a blue cast to it then it may have leaking valve stems seals.

I usually start by doing a compression test to see if there is an internal issue. If there is a compression problem then it is a head gasket problem. If the compression is fine then it will need new valve stem seals. Both cases will require some serious engine work be performed.

If you need to have this looked at, consider YourMechanic, as a certified mechanic can come to you home or office to diagnose the smoke and repair this.

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