They don't check this thread all too often. I'd recommend to call or email them: service@autuning.com
(714) 841-1000
Yeah if you haven't had a carbon cleaning, you're due for one lol. They do walnut shell blasting & follow it up with a chemical cleaner. They did mine a while ago at 55k, I forget how much they charged... it was definitely cheaper than the dealer though lol