08 gs 350....there are 2 middle vent and 2 outside vents on the dash. with the a/c on LO for both sides, the driver side middle and outside vent blow cold. but the passenger side middle and outside vents blow not as cold, feels like 10 degrees warmer. does this in recirculate and outside air....AND when i close the driver side vents, then the passenger side vents will blow cold, but once i open the drivers side, it goes back to blowing not so cold...weird anyone have a clue why. i had to recharge back in december, with no issues till now, driving me crazy why one side blows colder that the other?

thanks

 

Use a thermometer to check for sure what the difference is? Possible leak in the vent tubes to the passenger side? Or are the tubes for that side are routed longer, thus more time for heat to affect the incoming air on passenger side?

Just guseeing, those would be the possible reasons if and only if the thermometer proves that side's temps are indeed warmer.