I have this problem in my '07 Cooper S. I don't see smoke very often, but have been through (under warranty, thank god) an HP fuel pump & timing chain tensioner & loads of injector cleaner. The tensioner seemed to help marginally for a bit but didn't solve the problem. Most recently I was told my oil was low (1 qt). Ok, I topped it up and check it maniacally now, but it doesn't help. It's a daily occurrence that my car sputters and loses power up a hill - just for a few seconds. Enough to really freak me out but it's NEVER thrown a code over this and the dealer has not offered to clean the valves or anything. I run 93 octane, have tried octane booster beyond that, injector cleaner every couple of months, etc... I had wondered if it was a turbo bypass valve thing (I am from the world of Saab...) but the Mini mechanics just look at me like I'm crazy. This thread is useful but I wonder if there are any new bulletins or anything out there?

 

"Superknock" run a search in the forum and you'll find many threads.

Happens whether you're stock or tuned, only solution right now is to downshift to higher rpm's for hills. The extra load at a lower gear will cause it to "superknock". I'm assuming this is after a cold start and the first time trying to give it power during the drive?

 

SooperCuperErik - thanks for this info. The problem happens after 20 mins of driving on feisty backroads. It also happens cold but I try not to push the engine till it's good and warm.

 

Do you have a replacement part # for the rubber hose u used?

 

there isn't a part number. you literally go to your auto store and buy 1"ID rubber hose and a pair of hose clamps. I did this too.