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Theory of operation for BMW (Mini) 'VANOS' VVT system, P054B related
2011 Mini Countryman S, has an intermittent P054B which happens about 5 minutes after first start up on cold (below freezing) mornings. After it warms up you can start it again and no CEL. The research I have done relates this problem with cold starts but it sounds like the problem occurs immediately at start up, not 5 minutes later (when I'm guessing is about when the engine is warm enough for the coolant to start circulating so the ECM might be trying to change the timing.) I don't know the theory of operation though concerning what this system 'should' do at cold start up. It does have the correct type/amount of oil. The engine is not missing or running rough either and there are no starting issues.
Not wanting to be a parts changer I want to learn a bit more about how this system works before proceeding. Most things I have found on line give an high level overview of the system and list of possible symptoms, etc. I'm just puzzled about why the problem occurs when it does. My only guess at this point is that the exhaust side solenoid is sluggish when cold but works a bit better when warm. It seems like the solenoids are considered standard maintenance parts to be replaced at 70,000~90,000 miles and I don't know if these have ever been changed.
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