I will say Seafoam as well. However, Lucas just came out with a competitive product. I work for a major retail auto parts store and can see no difference between the two products. Check out the related video....
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I wouldn't pour any of these into the crankcase where the oil is. It will ruin your bearings. If you use a quality synthetic oil, you wont have any sludge buildup inside the engine.
Personally I use CRC Intake Valve cleaner. You insert the tube into the intake while it is running and spray the entire can into the engine. Go drive it hard to clean it out.
Here is the link http://www.crcindustries.com/products/gdi-ivd-174-intake-valve-cleaner-11-wt-oz-05319.html
I'd be cautious doing this with an ecoboost motor due to the carbon that can break free and end up between the cylinder walls and pistons or worse in a turbo. Ford has warned against induction cleaning in the past.