DONT! We get alot of Mini in that that have carbon deposites because of cheap or low grade fuel. The lowest I would go is Chevron 89 octane. Realisticlly you are only spending about 2 to 3 bucks extra per tank of fuel and its worth it. To clean the engine they make a kit the the dealer has and it runs about $300 to help clean out the deposites. And its not coverd by warrenty. You can get a lot of fuel for $300.