Hello,
Hope all is well and thank you in advance for any guidance!
I have a 2018 genesis g80, a GDI and was wondering what I can do to clean up any carbon build up so far. It's at about 90,000 miles runs great, I just ordered a catch to put on there, but I really want to clean up any carbon build to the best of my ability without having to spend the money for blasting it is there any other diy way of cleaning it up? Short story.. I recently had the P0420 code come up for a cat issue which cleared after putting in some emissions system cleaner, the came back a week after and I didn't do anything other than run the obd11 scammer but recently the code just went away on its own no cleaner just driving cycles. I'm wondering if the this is due to all that carbon build up hitting the cat, because it's weird that it went away on its own but came back after putting in the cleaner after clearing once.
The catalytic converter is probably on the bare edge off of acceptability. That's about the only time those "cleaners" do any good. Sometimes even changing gasoline brands will have the same effect.
The carbon that builds up on intake valves can be pretty tough stuff. I'd think that with that kind of mileage you'd have a lot of buildup and chemical cleaning may not be enough, but you could give it a try.
Here's a Scotty video on the topic:
I don't have any cars with direct injection, but I used to work for a plating company, and the plating techs would spray CRC non-chlorinated brake cleaner on parts before processing them. I've also used CRC engine degreaser to clean up a piston that I found in a junkyard during COVID. I cleaned the piston up myself and the plating techs plated the individual components making it up. The plating job came out flawless, so I can safely assume this would work pretty well: CRC GDI Intake Valve Cleaner 11oz | AutoZone
Hope that helps!
