I think the head-bolt is broken. Take a look at the 1:00 position on the oil filter housing. http://listings.boostmotorgroup.com/...ID=36&isLogo=0
No big deal as long they fix it for free.
If no codes are being thrown use Chevron Techron fuel injector cleaner (concentrate). It solves rpm fluctuating upon cold start-up. Also, for most BMW problems start off by scanning your car with the Peake Research Tool. It contains the actual BMW codes. If you want to register a newly installed battery for free (just buy a $10 cable) and google/download BMWLogger