The n62 common fault are the CCV "valves"? (Orange diaphragm). You can check for inordinate vaccum by pulling the dipstick while running at idle. Normal for the engine to stumble a bit when you pull but the vacuum shouldn't be crazy high.

You don't mention odometer. N62 will chew through the VSS and I suspect eventually in addition to smoke will allow enough air though to cause lean codes as well.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)