I have a serious problem with my 6 speed in first and second gear (usually in sport mode). When in gear, car jerks and bucks so severely, it almost feels as if the car is being held back. People who have driven with me when it occurs can not believe the extent. I have taken the car to the dealer many times for them to say the have been unable to find anything wrong. Within the last two weeks I went out on a test drive with the head technician, who certainly experienced what I have been dealing with for the last year. He said he has only seen this happen once or twice before. Just yesterday they had an engineer from BMW drive the car and claimed this was normal. It is absolutely impossible for this to be true, and based on what the tech. said I think he was only trying to cover his product. Has anyone ever heard of this before, and if so any recommendations? Desperately seeking the truth, Thanks!