Since taking ownership of my 2009 JCW Clubman R55 last May, I've had several occurrences of about a half second of lost power while accelerating followed by the appearance of two codes on full scans of the whole system with my Schwaben (Foxwell NT510) scanner. These are the alphanumeric codes in the DME engine management section of a full auto-scan (not an OBDII Pxxxx code) and are for superknock on cylinder 4 (or 1 or 3, etc. different cylinders each time) and a fuel cutoffcode for the same cylinder. No CEL and no stored or pending codes on an OBDII scan. I take note of the DME code and erase it, and it happens again only once every month or so. I scan it about once a week and the code doesn't recur until the same brief hesitation on acceleration occurs again. I've read that many if not most N14 R56 models tend to have these particular codes stored on them, so I'm not too freaked out, but wondering if there is a real problem that needs to be addressed (intake valve crud, Vanos issues, timing chain guide issues, etc.). I have less than 33,000 miles on the car (about 4,000 by me), and don't hear any suspicious noises on startup to suggest chain tensioner problems (just the sewing machine tap of the DFI), have new OEM plugs, and no other associated codes or issues.