This popped up on my FaceBook feed earlier.
http://www.enginecarbonclean.com
The reviews all looked good but they always do!
After a bit of reading the principle seems to be injection of a fine water based mist or "Hydrogen technology" as it's referred to!
It sounds like it may help with carbon build up but I'd be sceptical as to where the build up goes and how good 30 minutes of misted water into the intake can be for the engine.
Thoughts?