Can you translate your codes into English? I don't have them memorized.
But, it isn't necessarily the maf or 02 sensor. If maf, I think you would have gotten more codes than just bank 1 (sensor 1).
Also, if replacing any part on our car, don't start thinking about how to get an incorrect, albeit free part to work somehow...especially an electronic part.
If you need an 02 sensor, get the right part...a real bmw part or part from the OE supplier, whoever that is.
It does sound like you probably have an air leak, and lower intake boot is probably the most common one...but there are many vac hoses as you know.
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