After failing emissions 3 times due to high NOx I'm in need of expert help in diagnosing why. The limit is 5.0 and I've gotten 7.5 the first time, 8.1 after tuning it up & today 11.2 which shows I'm moving in the wrong direction.
I did find a crack in the intake 'accordian' and thought I sealed it well but apparently not which would account for some of the increase but even when I replace that I'll probably still be high since I started out high. I'm guessing I split that when I tuned it and put it back on.
Anyone dealt with this or knows the emissions well that can find what's going on?