[Ghawkins]

Since this is GDI engine, do I need to clean intake manifold like other GDI engine cars?
I can't find any maintenance schedule for intake cleaning, in fact there's no clear maintenance schedule for the car, it just says to read display for any maintenance reminder..

Not the manifold, but the intake valves. This may or may not be an issue many miles down the road. Some believe all direct engine engines eventually require the valves to be cleaned as they never are in contact with gasoline as in port unjection. Walnut shell blasting is considered the best method. Somewhat expensive however. Around $500.

This subject doesn’t get much interest in Honda forums. Maybe not a concern. Others should weigh-in.

 

[Ghawkins]

I didn't know about the cleaning requirement on GDI engines until my 2013 Kia Optima(also GDI engine) starts to consume couple quarts of oil between change.

I can’t imagine how the carbon buildup on the backside of the intake valves would effect excess oil consumption. No oil in that part of a internal combustion engine. Excessive oil consumption is usually a result of worn piston rings or bore damage. Oil can leak of course but that is not consumption.

 

[Ghawkins]

so, how come Honda doesn't recommend this cleaning even though this is GDI engine?
are they figuring that it's good enough until the warranty expires?

Your question is a valid one. Honda has used direct injection since 2013 and no real data has appeared in this forum regarding this issue. I have some reservations about chemical solutions for this issue. Does it really work? Does it have any downsides? Does Honda really have a problem with this? Hope others weigh-in. Just about the whole industry is using direct injection now.

VW has offered direct injection engines in the US since 2006. The first and second generations had carbon buildup but the third generation (2014 on) not so much. Apparently the EGR and PCV systems have been re-engineerd accounting for the improvement. I have a 2015 GTI (35,000 miles) in my garage alongside my 2018 Accord 2.0. Concerned about both. Catch cans seem to offer nothing on these late engines.