Originally Posted by G7HH
Thanks for the info. Very clear and easy to do. As far as what battery to use, I brought my old one in to O'reillys and they just matched it for me, easy. I didn't bother to register the battery with the car computer and I haven't had any issues; been driving it for three weeks now.
Report back in 1 year.
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