Drove the ML350 last night and no check engine light at all. Had been on for a week after leaving the MB dealer. I cranked it up in the driveway and noticed no light. I had the windows down and no AC on. I drove it for a couple of miles and turned it off. Cranked it up again and no CEL. Did this for three or four times. Not on at all. If it were the balance shaft and chain it is my understanding that the light would appear and not go off.