Two problems related to engine have been reported for the 2007 Mini Cooper S. The most recently reported issues are listed below.
2007 Mini Cooper S engine rattles loudly for the first 30 seconds to 2 min. After startup in cold weather. Caused by cam tension issues. Min has worked on it numerous times. It is now out of warranty but still having problems. I happens on an almost daily basis on cold days.
Engine rattle at start up, engine will not maintain idle when ambient temperature too cold (as high as 20 deg f but more common as temperature drops) and can even die. Engine hesitation and stumble while accelerating and while maintaining highway speeds, regardless of engine and ambient temperature. Lack of engine power. Car may seem to be running fine but when accelerating the engine will stumble and hesitate, much like a missing cylinder, this causes the car to accelerate slower than expected regardless of throttle position. This can create an unsafe condition. Seems to be most pronounced at part throttle between 2000 and 3000 rpm but is still present at higher speeds and more throttle opening. Can also make the car stumble very badly when starting from a stop, causing the car to move forward a few feet very slowly before accelerating at a somewhat normal pace. This effect is similar to letting out the clutch too soon but happens even if rpms are brought up to 2000+rpm and the clutch is slowly let out.