Hey guys, I'm in dire need for some technical advice. I've been having this issue on my cooper S R53 for a couple of months now. It's some sort of a rattle noise coming from the left supercharger horn or somewhere down below. Noise would persist for the entire drive but more prominent during cold start. I've replaced timing chain tensioner but to no avail.. Next plan would be to remove the supercharger to check on the PTO / refill the oil. Fingers crossed

Video link
-cooper s r53 2006 checkmate edition

 

Push you clutch in and see if the rattle goes away...
A throw out bearing on the clutch can rattle...and sound like it is from around the SC.

 

Forgot to mention it's a Aisin automatic

 

Did you figure this out? was it the belt tensioner?

 

I know a great fixing center if you need, guys.