FWIW, the new 3.0L S/C motor is so far not exhibiting any carbon buildup issues.We have people checking and have 10,20,30,and 45k pictures and so far, so good. They began running a higher coolant & oil temp which brought over-all heat way up. (EGT's are higher on this S/C motor than on the previous turbo applications) They run the motor much hotter than before and even on the RS5, they bumped the average oil temp up and it's supposedly helping.
One thing we know for sure after years of documenting issues, is that the harder/ longer the car is driven the slower the building and likelihood of issues.
People who drive 2-10 miles to work and barely get any heat in the motor had major misfiring and power issues by 10-20K miles. By contrast, people who drive 50+ mile commutes had every little buildup, even at 100K+ miles.
I've been trying to blow the car up for years, I have a 60+ mile commute daily and it gets beaten and heated up every day. Still runs & idles like new w/ perfect vacuum. I'm waiting for the turbo to go eventually so we can do a motor pull and check everything and refresh/ upgrade.
Until then, I'll just beat the shit out of the car until it goes. :dumb: