I don't know if they work or not. Seems kinda late at 80k to throw one on now.. If mine ever exhibits symptoms I'll have it walnut blasted and probably try one then.
All direct injection motors will be prob to valve issues, reason is we don’t have port injection spraying fuel on the valves keeping them clean. Catch can will slow down this process a lot but that’s your only defense, STP makes a injection cleaning system that you can get at AUTOZONE and if you check your valves before with a scope and then after you do the proces, the valves are almost perfectly clean. So I do this every 5-6k miles along with my catch can.
I just installed an auxiliary fuel system that uses both direct and port injection. I also capped all inlets other than outdoor air into my intake system including the OEM manifold.Sure. But it wouldn't be illegal to install a factory catch can, or to ditch the direct injection, or to use a combined direct/indirect injection, or to design valves and/or an inlet system that make carbon deposits less likely to form, or whatever - you name it.
I'm sure there are solutions. Sweeping the problem under the carpet isn't one of them.
If I have to have someone else do it I will look for someone to walnut blasted the valves.Food for thought - you don’t want chunks of carbon breaking off and entering the combustion chamber and ultimately onto the turbo.
Blasting the valves has been the go-to solution. The most common thing you’ll see is walnut shell blasting.
Stating the obvious here, but the intake manifold is removed and the cylinder being blasted obviously needs to have the intake valve closed. The shell media is blasted into the port and it clears the carbon debris off the valve, then all the media is vacuumed out of the intake port. Rinse and repeat for the other cylinders.