Hey, I joined just to try and clear the air with the Ecoboost and then with DI in general.
DI and turbos have been around for decades, DI being much older of the two. DI only recently gained popularity because of computer controls to better allow for more precise fuel management. DI engine have several advantages, one being it can fire nearly time except for on the combustion stroke(but it's best only to fire at certain times). The low end torquefound in DI motors is akin to diesels when they accelerate, they produce a large amount of Particulate matter. The revision in the ecoboost is to better fine tune the injectors, gasoline injectors only have so much pressure, and the injectors only have so much duty cycle. So when you have a high output motor you sacrifice some resolution by going up to bigger injectors. So in order to better get a handle on emissions they use the port injectors to supplement the direct injectors, this allows both the DI system and the port system to be more precise and have a better range of operation.
Fords system to my knowledge is not prone to carbon build up. That's with personal experience and some research on the matter.
As to using a fuel induction service, most manufacturers' don't recommend it, it can burn up /clog your catalyst. If your car is having problems, the induction service only mitigates some of the symptoms if any.
Yes, fuel wash and swirl past the valves with detergent gasoline can help keep them cleaner than they would otherwise be, but a good DI setup will plumb itself in such a way that it doesn't matter. There are good and bad DI systems, I don't think anyone should second guess the ecoboost motor because of it.
Odds are with most modern day cars, your engine will out last your frame as long as you properly maintain it. Sure things might go wrong here and there, but quality is vastly better now a days, even compared to just 10 years ago.(I might not be able to make that statement much longer with all the trucks and things going to aluminum)
