AC only blowing cold through driver's side vent.
 

Long story short, I have a 2004 X5 4.4i and the ac was not blowing cold at all. Talked to my dad's indy friend and he said normal operating pressure for the ac system is 25-30 psi. My dad put his guages on it and it read 25 and so we put a little more 134 in to get it to 30 and the ac worked much better for the next week. But as of a week later, the ac is only blowing cold through the drivers side vents and not the rear or passenger side vent.
I've been reading posts that say it's an improper charge but how can it be blowing fine on one side and not the other. Is there some type of door or valve that's suppose to be opening or closing that's not working properly. Thanks!

*in for the answer* same thing is happening to me.

I have been told that this is a designed failure for low freon. Driver side will stay cooler than passenger. I had the same problem, added more freon and the passenger side cooled back down
Also check the heater valve. It could be stuck open. Tap it with a rubber mallet and move the temp from hot back to cold and see if the valve closes and the AC blows cold again.

This happened to me. It is because of low gas.
I put it down to there being 2 evaporators under the dash.
The gas flows through the drivers side (passenger in my case) first, therefore the pressure is lower by the time it gets to the passenger side evaporator.
This did my head in until I had the system vacuum tested, found a small leak in the compressor, replaced it and refilled with gas and now it works fine and has been for over a year.
So yeah, sounds like you may have a leak. I know they only hold a small quantity of gas, so they must run a fairly high pressure.

thanks for you help guys. more help will be appreciated, but I think I will have the system tested to see if we lost any of the charge we put in and then vacuum tested to check for leaks.