Carbon buildup in direct injection engines

[tux]

Hi all,

 

I'm looking to upgrade my ride and with the current tax structure, all affordable cars (up to C-HR) come with Turbocharged direct injection engines. 

I have seen some articles on the internet that carbon buildup in intake valves is a common problem in GDI engines as there is no fuel in intake manifold to wash backside of valves. So, oil residue from crankcase ventilation will deposit in intake manifold which will cause issues.  Also, carbon buildup in injectors is very common as injectors exposed to combustion chamber.  

 

Are these "real" concerns in current hot selling small turbo engines which require frequent expensive maintenance? 

[iRage]

Yes but no...yes DI engines can be prone to what you have indicated and using additives, etc does not necessarily help break up and clean any carbon build-up. However, DI engine'd cars have been around for a while even in SL it just have not been your average econo boxes that came with them. As long as you

a. keep the car properly maintained (carry out proper scheduled maintenance and preemptive maintenance)

b. use fuel that is not crappy (fuel in SL is not the best but its not all doom and gloom either as long as you go to stations hat have proper storage tanks, etc...and is reputable) 

..you will be okay.

[Twin Turbo]

Hope you don't regret your choice,based upon the data you already know.

[ajm]

are there any GDI vehicles imported by any official agent?

Then a feasibility study with local fuel quality would have been done.

[tiv]

Don’t they have an additional injector to spray a mist to the valve?

and isn’t this due to the egr?

both my Mitsubishi’s have egrs and I’ve cleaned them every 20k, this is for diesel though, the carbon buildup was horrendous! 

[ajm]

  On 9/2/2019 at 6:49 AM, tiv said:

Don’t they have an additional injector to spray a mist to the valve? 

and isn’t this due to the egr?

 

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The injectors in the manifold are for improving emissions without installing a particle filter.

AFAIK they only spray in certain RPM ranges (eg:low end) but could have a cleaning effect of a conventional port injection.

But I doubt if the 1L econo boxes can afford to have a 6 Injector(3 direct + 3 port) system.