Hello guys, i found this forum, very helpful. maybe someone can help me with my 2000 LS:

My AC never works correct,in summer time the driver side blows room temperature and sometimes even hot air, with the termostat set at 60.

In winter time, the heat sometimes blows cold for a while on both sides, but most times only on driver side. after a while it start to work correctly. But God forbid to change the direction (from blowing through the dash to windshield/floor for example) , from hot air , it changes to cold right away!!!! But , the interesting part is that i can still feel a hot air trickle through the dash vent, and cold air through the windshield/floor vents. I was thinking that it might be somekind of electronic problem, sometype of module be defatctive, but then sometimes when i change from dash vents to windshiled i can hear noises in the dashboard, actually like grinding noises???!!!!
maybe i have multiple problems?
Any input is appreciated.

I believe you're going to have to take it to the dealer. I assume no idiot lights are on. My '04 A/C was blowing cold on one side and warm on the other. It was at 48K, so the dealer repaired it, whatever it was. I do know it took many hours, not something cheap, I imagine.

My '03 Ls is doing the same thing. Cool air on the passenger side and warm air on the driver side. My doors are not creaking. If I disconnect the hot water solenoids I get maximum heat both sides. Hmmm....