There are a lot of hoses right there. Many of them are vacuum and would definitely explain your HVAC issues. There is also the breather for the front diff. One end is on the diff, the other end just sits on the top of the shock stud. It might look like a loose hose to the untrained eye. Post a pic of said hose and we can definitely let you know what it is.
2002 Overland - 4.7 HO, "Select-Drive", 4" RC long arms, TAG front winch bumper, 32" BFG KM's, 3" exhaust, Magnaflow hi-flow cat, Flowmaster 50 series