E46 (1999 - 2006)
I've searched quite a few OAT issues, but never have I found this one.
If the AC is off, all is well. The OAT registers properly. The minute I turn the AC on, it starts climbing about 2*F a minute !, even at highway speeds. This is the OAT, NOT the coolant temp !
If I turn the AC off, it will...