Q: Blue smoke after starting the car

asked by on September 21, 2016

Several days ago I went to start my car and there was a huge amount of bluish smoke when the engine started running. This has never happened before. The car sat for the night before I started it the following morning. What might cause this? Is this a serious issue?

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Blue smoke usually indicates oil getting into the combustion process - not a good thing. If you had your oil changed the day before, check the oil level to make sure it wasn’t over-filled. If you car is accumulating some mileage (nearing 100K for example), it’s possible that the valve stem seals (exhaust) are not sealing well. This normally occurs gradually, with a small amount of blue smoke after an overnight or extended period on non-use. A professional mechanic, like one from YourMechanic, can help diagnose the smoke problem and have it addressed accordingly.

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