Two problems related to gas recirculation valve (egr valve) have been reported for the 2009 Mini Cooper S. The most recently reported issues are listed below.
This is the 2nd time this happend the car started to acelerate by its self when stopped and the brakes couldn't hold the car back, I then put the car into newtral, then into park tapped the gas and the car acted normal. It was like the car had a mind of its own and just started to go without my foot on the gas pedal . The last time this happend was a year ago . I thought it was a fluke but now it happend again, I am a very good driver but after this happend again I think I might just get rid if this car . . . It reminded me of the movie chritine when the car had a mind of its own. I was stopped at a light with a car in front of me, the weather was 45 degrees and was driving for about 15 minutes already when it happend.
I purchased this car with 24k miles on it. It now has a little over 28k miles. It has been starting and running just fine, until the weather turned colder. Now if the car sits outside for a few hours with the temp below about 45 degrees, the engine rattles and sounds horrible when I first start it. This is a very loud rattle coming from the passenger side of the engine. The noise is so bad that I am afraid to drive the car until it warms up and the sound goes away. After a little research online, I am shocked to see how many people have this problem and that it is the timing chain tensioner and guide system. I wish I had researched these cars before making a purchase because now I own an expensive problem.