Thanks for the response. Something else I noticed today while driving. I was at highway speed (65) and I noticed that center vents were letting a bit of warm air through (warmer than ambient) so I shut the center vents off and switched the A/C to see what would happen. Sure enough, the left (drivers) vent started blowing cold air. Opening center vents again only provided warm air and the cold air in the left duct became warm too. What am I looking at here?