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carbon buildup on engine valves

  1. Carbon deposits

    Welcome New Members
    I have a 2012 Mini R58 S and his name is Tom. I bought him in 2015 when he had 30k miles. For the last year Tom has been acting up. Engine misfired so spark plugs and ignition coils were replaced. A month later I felt the same misfiring and loss of power when I hit the gas. Turns out it was...