Skip the auto shop - Our mechanics make house calls

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

asked by on

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.

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Maintenence warranty

As you know, with any car the life expectancy of it depends largely on the maintenance schedule the owner has maintained, the driving conditions it is subjected to, the driving habits of the owner and many other factors. As with...

Q: My Check Engine Light is on - code P0025

Hi there. For your 2010 BMW, the [P0025 is the OBD-II error code] that (https://www.yourmechanic.com/article/p0025-obd-ii-trouble-code-camshaft-position-b-timing-over-retarded-bank-2-by-jay-safford) indicates the Engine Control Module (ECM) determines that the exhaust variable camshaft timing for bank 2 is more retarded than what the ECM desires. ...

Q: I don't have a fuel cap, its say check fuel fill inlet

The problem is in the fuel filler neck not sealing and should be tested using smoke test. You should have the neck replaced and the system checked again for leaks using smoke through the test port in the engine compartment....

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.