I run M1 10W30 in my '17 Sonata GDI for these reasons : Low NOACK of approx. 6% and low Viscosity Improvers - both equate to lower intake deposits . I also run only top tier gas and use a bottle of Gumout Complete Fuel System Cleaner just before every oil change (5,000 miles) and drive mainly around the 'burbs in "Sport" mode to keep RPM's up over 2,000 RPM's while driving so the engine doesn't lug . *I've done all I can do to address intake valve deposits with the above approach , so far so good - but only 10,000 miles driven so far ...
Originally Posted By: webfors
Let's hear the experience and opinions flow.
What oil brand, viscosity, and spec is the most resilient to contributing to intake carbon deposits on GDI engines.
I've read many threads, on many forums, for many different types of GDI engines. There is consensus that a full synthetic (whatever that means...?) shows clear signs of reducing the intake deposits. I suspect because of syns tolerance to high heat and a higher quality base oil with lower noack.