Occasionally when the adaptive cruise control is active, the collision warning will light and the brakes automatically applied even though there is nothing in front of the car. This has occurred on a straight, flat road with no shadows, undulations, or cars anywhere in sight. This is a huge safety hazard since it has happened with cars traveling immediately behind me at a high rate of speed. BMW techs cannot id the problem and say they have never heard of it. The problem is infrequent and highly unlikely to occur during a test drive. Met today with a BMW na technical service expert who insisted that I was 'confusing' this problem with the system's normal operation. Not so. My lease ends in 2 months and I don't want the next owner to get rammed from behind.

- Orrtanna, PA, USA

When at a complete stop the car hesitates to accelerate. There is a two - three second delay after you step on the accelerator. This has resulted in almost being hit broadside on several occasions. The car literally drifts for a few seconds before responding. Way scary and very dangerous. Afraid to cross lanes with oncoming traffic. The fuel saving auto/on/off has always been disengaged when this occurs. Not using sport or eco setting either. Very unsafe car. Problem has existed over the past 14 months since purchased new. Have complained about problem to dealership and BMW North America numerous times. BMW tried to update software but it didn't address problem. Others on bimmerfest in the usa are also stating they are having a similar problem. Please help. I bought this car new at a price of over $40K.

- Vienna, VA, USA

'specifically bought this vehicle for the active driving assistant and acc stop & go + active driving assistant as I use cruise control as much as possible and have the following issues: Othe stop & go does not remain active long enough to work through stop light timings othe active driving assistant slows down impropriety for vehicles parked on the side of the road othe active driving assistant creates to much distance between the follow-on vehicle allowing cars to cut in front of me odoes not work correctly in misty rain or in direct sunlight odetection of follow-on vehicle is not consistent ' sometimes slows down and stops at normal rate and other times it is a hard stop or emergency breaking odoes not consistently detect that vehicles are in front of me and I have to intervene in stopping vehicle many times oemergency stop has happened several times when no impenitence is in front of me ' potentially worrisome because cars could slam into me.

- Issaquah, WA, USA