Why?
Carbon buildup is barely an issue for the 2.0T
Im guessing your referring to a larger, NA direct injection engine that relies on its air flow ports a lot more then a turbo charged 2litre. However, it will still help you reach higher figures - plus its nice knowing theres no gunk in there
Also, is it not possible in extreme cases for a chunk of carbon to break off and do some damage to the cylinder/pistons?
TBH, I spent along time manually scrubbing mine - so am just trying to justify it
I do however concede that the "carbon clean" offered by companies such as terraclean, enginecarbonclean etc. where they don’t manually clean the carbon and therefore not actually remove any carbon – is utterly pointless and a waste of money.