I know this is an old question, but can't find a final answer. Do newer 2.3 Ecoboost engines still have issue with carbon build-up? There had been reports that earlier ecoboost engines had this problem, but was thinking Ford had resolved?
I've seen teardown of a '19 2.0 with the issue. And here's a borescope of the inside of my '18 2.3 that you can see inside the intake with obvious carbon build up. You'll also notice the coolant weeping from the headgasket which is another problem these engines suffer from more than is generally thought.
I really can't imagine that Ford has solved the issue and not been bragging about it. Especially since it affects every DI engine that I'm aware of.
I don't think there's anything they can do about it, short of installing dual DI/PI injection or a catch can. And I'm pretty sure they'll do neither, because the carbon build-up doesn't affect them in the least.