Yes I took the plastic wrapping off the filter! I checked, no codes. I will try reinstalling this weekend and see what happens. Could it have been WD40 on the IAT? Could it have been that the ECM not recognizing it. The 3 engine start deal? I dont know enough so that is why I ask so please bear with me. I would like to be able to use the BHAF for the obvious reasons (lower EGT's, Quicker spool up, better fuel mileage, & longer filter life). I only attained one of the benefits, lower EGT's. What Gives?