Q: Blue Smoke After Cold Start

Hello and thank you for contacting YourMechanic. Blue smoke coming from the tail pipe is an indication of the engine burning excessive engine oil. Check the PCV (Positive Crankcase Ventilation) valve to determine if it is operational.

The oil that is burning off could be caused by two things: either the PCV valve plugged up and forcing oil into the combustion chamber, or the valve guide seals are not working causing oil to bypass the seal and seep down the intake valve and puddle up into the combustion chamber.

Now, on the 2012 BMWs with Turbos, it is common to have a turbo leak oil into the intake and make the engine suck in excessive oil after a shut down. Remove the intake and see if there is any oil coming from it. If there is oil saturated inside the tube, then you need to have your turbo rebuilt or replaced. If there is no oil in the tube and the PCV valve is okay, then most likely the valve guide seals are worn. A little puff of smoke is normal for the 2012 BMW with turbo, but not for more than 15 seconds.

I recommend having a professional mechanic, such as one from YourMechanic, check out your engine and determine the cause of the oil consumption and the blue smoke coming from the car.