You are having all sorts of the problems huh? I just replied to your other question about the transmission... As far as the HVAC concern you have posted here, let me start off by saying that these cars do not use vacuum lines to control opening and closing of the doors.. All the doors are controlled electronically by little motors attached to the doors... If you have the time, you can try to diagnose this... The only problem is that you need to remove about half the dash just to access these... Does it sound like it is switching at all? if you are lucky, the door is just binding.. but it is probably going to be electrical... Taking your car in to have this looked at could either be a positive experience, or it may backfire on you, as you do not know whether the problem is something that can be fixed without taking the dash apart... like I said though, if you are the type who likes to learn as you go, then you can start by finding a manual with some wiring diagrams, and then if need be, carefully take apart your dash.. hope this helps a little bit.. let me know if I can answer anything else.. good luck!