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Q: White smoke coming out from exhaust, what can that be?

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It is a 2010 BMW 550i GT, white smoke coming out exhaust when starting. When driving, hitting gas. Is it head gaskets or CCV valves?

My car has 82 miles.
My car has an automatic transmission.

A: Hello, thanks for writing in. I’d be happy ...

Hello, thanks for writing in. I’d be happy to help.

White smoke from the exhaust can be caused by a few things. First off, keep in mind that white smoke coming from the tailpipe after a cold start can be steam from water condensation in the vehicle’s exhaust system. The steam will usually go away once the car has warmed up. It may also be possible that the issue is related to the head gasket. A bad head gasket can cause smoke from the tailpipe if coolant enters any of the combustion chambers. If this is the case the vehicle may also be overheating. I would check the oil filler cap and dipstick for any signs of coolant contamination that may indicate the possibility of a blown head gasket. If the engine is not overheating then it may be possible that an issue with the CCV/PCV system is causing the smoke. A bad CCV valve can also cause smoke from the tailpipe if any oil from the crankcase gets sucked in by the engine through the PCV system. I would start by trying to figure out if the issue is head gasket related or not, and go from there.

If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make any repairs as needed.

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