R56 Cooper S engine knock when accelerating

[j87d]

I've had my 07 Cooper S since APR this year and have been having some problems with it ever since then. My car had this intermittent acceleration issue, which I was pretty sure was carbon related. Did some minor fixes to it, but recently the car has been misbehaving when accelerating, usually in third/fourth gear.

The best way to describe it is a pinging/sparking noise coming from the drivers side of the engine bay, and at the same time as the noise the car loses all acceleration, before kicking back in again. The car has no fault codes or lights on, but it has also done it before when accelerating gently, although not to the same extent. Anyone else experienced this before?

[S8RAH]

Yep. It was carbon related. Mine had a decoke and it fixed it.

[j87d]

Thanks for the reply! Did u get this done by MINI? Ive been lookin at a new thing called Terraclean aswel, it was on this programme called wheeler dealers. Meant to chemically decarbonise your engine.. Did it restore ur acceleration fully too?

[S8RAH]

Mine was still under warranty so MINI paid. They actually put a new bottom end in but I'm not sure that was 100% necessary . I saw that thingy on Wheeler Dealers - looked so cool and a lot less expensive than taking the head off.