That was one of the major problems while it was at the dealer. I had taken the car to a local bimmer/merc shop and they said they problems were beyond their abilities. While there they cleared all the codes in the car. So when the car was hauled to BMW they had no history of any problems in the car. Because of them not finding anything they went by what I told them was happening and they put a new EHC module in the car. This did not fix the problem at all.