I plan to buy a 2014 Mini Cooper S Countryman but was very concerned by all I was reading concerning carbon build up on the back of the intake valves, due to direct injection. The lengthly thread on this forum made walnut shells a certainty for my yet-to-come Mini Cooper's future.
However, I have come to the realization that many cars use direct injection, including a car we presently own (a Mazda CX9). Even another car I like, a VW GTI, uses direct injection to deliver fuel to the cylinders. This is hardly a Mini Cooper-specific problem.
I wonder how other manufacturers address the carbon build up problem.

 

My wife's CX-7 and my old RX-8 had Carbon build up issues as well. you are correct that many people seemingly only associate carbon issue with Mini's.....as 90% of Rx-8 owners know it is an issue due to the rotary design as well, but SUV owners are usually clueless of the problem.

 

Audi has added a second injector in the head to wash the intake valve.

 

I've read that the most recent redesign of the oil vapor recovery system on the MINI has helped a lot with the problem. I think other direct inject cars might have a better designed oil vapor recovery system to deal with the problem.

 

The later n18 engine designs had major changes to the head design. It's not showing up as a huge issue like the earlier cars.

 

What year did they start using the n18?

 

2011 cooper s models. if i were the op i wouldnt worry about that specific issue.