Hi all I am in need of some advice for my BMW 645 Ci (2004) car .. I have noticed lately, that when I pull away after being at idle, in traffic or traffic lights for a long period, , I get a cloud of blue grey smoke from the rear of the car. This "smoke' does not appear while driving normally, at high speed or accelerating. Engine sounds and runs fine. I thought, it might be a slow oil leak and its dripping onto the exhaust. But, I am no expert. Just to add - It only happens when the car is running at its correct temperature ... Any advice from anyone is much appreciated Best Regards Mike