I replaced the thermostat/housing assembly and the coolant transfer pipe on my 2011 MCS N18 just this past Thursday. Pulling the intake definitely made the job MUCH easier. Since it was right at 100k miles (100,483 to be exact) I figured it would be interesting to check the carbon buildup on the intake valves. I bought the car used with 21k on the clock, and I doubt they were cleaned before that. All 8 valves looked about the same. It was a PITA getting my phone and light in there at the right angle simultaneously. These are the best pics I could get.

 

Good pics. They don't look too bad for 100k miles. Are you going to get them cleaned?

 

Thanks. Yeah, looks like the N18 doesn't coke up as badly as the N14. I may have them cleaned, if I can get it done for a decent price. I do drive this little monster pretty hard, maybe that helps to keep the carbon at bay somewhat?

 

Yep, looks like in good shape the N18 does not have that much build up as the N14 does, the long drives and reduction of short stop and goes reduces the build up from what I have seen. When I talked to MINI techs they said this also. If you need the DIY kits we have them.

 

That doesn't look that bad at all.

 

Gotta love direct injected engines. Check out what my brother's valves looked like in his Mazda 6 (turbo) after 2,700 miles. We had the intake off to install the water/meth injector.

https://forum.mazda6club.com/engine-...re-series.html

 

I did walnut blast on N18, didn't make much of a difference, super clean compared to most N14 I've seen.