What is your question?
I have a 2016 3.8 Genesis Coupe with a GDI engine. I've read that on a GDI engine, blowback crankcase fumes and contaminants recirculated back through the PCV valve into the intake manifold, tend to carbonize on intake valves because with GDI, fuel is injected directly into the combustion chamber, not into the intake port above the intake valves - with no gasoline running over the intake valves to keep them clean and act as a solvent on crankcase contaminants, GDI intake valves tend to accumulate serious carbon deposits. Millions of cars today have GDI engines.
What is the best approach:
1) Take it to a shop or dealer for a total system cleaning (around $220 or more) every 20K miles
2) Go to Valvoline or Jiffylube for a 'fuel inection system cleaning (about $90)
3) Buy off the shelf products and do it yourself
Lastly, Is there any way to inspect the intake valves for actual need, and to assess post-cleaning effectiveness, such as some kind of endoscopic inspection?
What makes this problem better or worse?
Car only has 22K miles; no symptoms yet
How long has your 2016 Hyundai Genesis had this problem?
Car only has 22K miles; no symptoms yet
Regularly scheduled engine service using Hyundai recommended oil and filters as well as recommended fuel type will certainly help reduce or even eliminate crankcase borne deposits.. Yes, there are a lot of direct injection engines out there. Good luck and happy motoring !