Sounds like the oil separator but think about the failure mode. It can freeze, and your idling it won't help, it will extend the warm-up time. If it freezes open oil can be drawn into the inlet manifold by engine vacuum and you get smoke out the tailpipe. No leaks, though. If it freezes closed the crankcase can get pressurized and it pushes out any gasket it can, usually the valve cover gasket first. Oil leaks out onto the exhaust manifold and you get smoke up front, but not out the tailpipe.

White smoke is usually coolant, not oil. Can be hard to tell, though. Since you had problems before this (valley gasket, low coolant) you could have multiple problems, making it harder to diagnose.

Start by figuring out where the leaks are coming from. And add oil before running it.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
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