Is Carbon Buildup a Problem With Direct-Injection

[John_Conrad]

http://www.autoguide.com/auto-news/2015/...n-engines-.html

The entire article was interesting, so i won't paraphrase or quote anything and let you folks more knowledgeable in this discipline discuss.

 

[RooflessVW]

Can confirm from my time at VW. Dirty valves first show themselves as a MIL for multiple cold-start misfires; the carbon softens after it warms up but the engine will still have reduced power.

I saw it most commonly on vehicles with a combination of over 60k miles and no prior maintenance history, leading me to believe that light-footed driving and quick lube oil changes exacerbate the situation.

 

[Solarent]

Yes. Intake Valve deposits are a major issue with GDI and TGDI engines. They are also an issue with PFI engines - however the minimum detergency levels mandated by EPA, CARB and others helps to mitigate this issue in PFI engines. As mentioned in the article (and in the video I linked to) now that fuel no longer washes over the intake valve, cleaning and preventing these deposits is now much harder.

The industry is currently working out new options - including GDI and TGDI air intake cleaning services that help to maintain this issue. There is also greater emphasis on Top Tier fuels, and even further discussion around beyond Top Tier - just look at Shell VPower, Costco Kirkland signature, BP Ultimate /Invigorate.

If you have a GDI or TGDI engine - use Top Tier Fuel, Drive Highway miles, get an air intake service if available at your service center. I've seen engines with issues within the first 10000 miles of service.

 

[Jetronic]

they sure sound likes diesels with dpf's...

Quote:
If you have a GDI or TGDI engine - use Top Tier Fuel, Drive Highway miles, get an air intake service if available at your service center. I've seen engines with issues within the first 10000 miles of service.