Ok so I installed a S&B cold air on my 2018 about 3 weeks ago. I did a lot of highway driving put on about 3,800 miles and one day about a week ago I’m filling up and I left the engine running, something I never do and I don’t even quite know why or if it’s just a stupid habit but right after that I get down the road a ways and see my engine light is on! Oh boy here we go, only 19,000 miles on it, so I bring it to my mechanic and he brings up the P2459 which is obviously DEF related, we don’t erase it so I can bring to dealer. I bring it to dealer and then they call me and ask when was cold air put on, I tell them and then they blame it on that cause they say it has to do with how much air is going into motor! I think this is a crock of “____”, and they were also supposed to fix a clunk in steering which they couldn’t figure out until I went back to dealer and showed them. Bottom line this dealer is a bunch of clowns but can anyone tell me if the code and the cold air intake could even possibly be related?