I really dont get it. I have a 2012 KW 660 with a 450 isx cummins with 293xxx miles and 8593 hrs. However it always pulls up the stupid emission code. Ive taken it too KW four times. Twice in my hometown and twice in dallas. Yet it always pulls a code. They say they cleaned the filter they say they changed the filter. I say its a piece of junk. Its so stupid. I mean i just get it fixed during blitz week get it back run tuesday. Do a total of 1000 miles and it does it again. Does anyone have any clue why it does this.