Heating problem! Sometimes the heat in my 2008 Nissan Titan works, sometimes it doesn't.. it will work for a few months, then stop for a few months. Blower works fine, a/c works fine, coolant level is fine. Only oddball thing its done, other than randomly deciding not to work, is there has been 2 different times that I've had the a/c on low then it randomly would blow, full blast, for about 3 seconds, then drop back down. Its a manual knob for the blower control.. if I turn my a/c all the way cold, it doesn't blow cold.. has to be one click above it. Any suggestions?

Cars & Trucks - Nissan - Titan - 2008 Nissan 2WD Titan