I have an '05 king ranch PSD that I just purchased a couple weeks ago. When I bought it the truck already had magnaflow exhaust installed and an intake. (forget which brand). The other day I cleaned the air filter and reinstalled it. The following day while towing ~3500# I got the "check air filter" message on the display:dunno:. The only thing I have done to the truck since purchase is installed the 3 standard custom tunes from innovative diesel, with an excalibrator 2. Any Ideas why I would get this message with a newly cleaned air filter. Could it be a bug in the tunes? Thanks in advance.