2012 R58 JCW (N14) with a RMW tune. This started a little while ago. When using 1/2 throttle or more the motor surges from 2500 rpm to 5000 rpm then the surging stops and pulls like it should. This surging is very rapid, at least once a second. The car doesn't throw any lights. I do have a Sprint Booster on it so I set it back to the stock map think- ing that might be it but no dice. It still does it. Any thoughts? Also, the car has a Scanguage and the map goes up to 34.0 but no higher. Is that telling me something? Thanks.
Just a wild guess, Is the throttle body clean? Have you checked all your vacuum hoses? Bad sensor MAP or TMAP I can't remember what the R56 has. Sorry not much help