Hi there, my name is XXXXX XXXXX X'X a BMW tech. Hopefully I can help you today!
Those codes are related to cam timing and misfires. If the car is running ok I would look for an unplugged sensor wire and if it's running rough I'd look for a loose coil wire.
A lot of stuff probably got unplugged when they oil separator was done and it would not surprise me in the lease if some was left unplugged or was plugged in in the wrong location.
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Thanks and good luck!
car starts fine idles rough starts and stalls when cold out
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