One problem related to engine noise has been reported for the 2008 Mini Cooper S. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Mini Cooper S based on all problems reported for the 2008 Cooper S.
When the car accelerating on the first and second gear, there was a small jerking motion. Took it to the shop and they didn't find any problem with the car. One the day of the incident date, 01/08, when I started the car, the car have a loud engine sound, sounds like the car is chocking for air. The engine light is on with the rpm pointer running up and down (gas paddle is untouched). Took it to the dealer and the next day and they found there is oil leaking from the oil feed line to the turbo. $1200 to replace the part. Did some research online and found many Mini owner had the same problem.