Best way to clean valves on this direct injection engine?

[BMWTurboDzl]

No just trying to ensure the car stays in top shape. It was a big investment.

Don't worry about it unless you start having drivability problems.

 

[billt460]

If you're that concerned about it, run a can of Gumout Multi System Tune Up through it once and awhile.

https://www.walmart.com/ip/Gumout-Multi-System-Tune-up-16-oz-Automotive-Additive-510011W/43913005