I have a 2003 E46 320CI M Sport coupe. Every now and then a strange occurance comes on. It is difficult to know where to start to look for the problem. I can brake change down and accelerate and sometimes the car then starts to jerk with what appears to be a misfire, the only way to clear it is to dip the clutch, flip the accelerator, let the clutch up and accelerate away.3 times when this has happened I have driven the car straight to the local BMW dealership and they have carried out a diagnostic check which has shown nothing amis. Has anyone else had a similar problem. The car has done 18200 miles and has had all necessary service checks as and when required.