Air Cond. blows cool air on right side of dash-not on left

Hi- I am new to this forum and need some suggestions please....I love my bonne but every summer I have the same ole problem..the air conditioning system is whacked! I bought her used and the previous owner had the same problems even after having pontiac service it. The problem is weird....I get cool air to blow from the drivers side but only hot or stale air blow from the passenger vents. I keep thinking something is blocking it ,but I do get the same amount of forced air out of the vents. Being a single mom- money is tight and my bonne is black in color and its hot hot hot here in atlanta....any suggestions as to why this is happening? Thanks so much!

I have almost the same problem with my 98 Grand Prix GTP. Except it's opposite. At first on a hot summer day it blows cold air out the passenger side and warmer air out the drivers side. Once I get down the road a couple miles it evens out. Although the right side seems to stay a couple degrees colder. Anybody know what's the deal?

made a mistake- it Will NOT blow COOL air out the right side but will on the drivers....was begginging to think it was something to do with the airbag....sucks too- because my car is BLACK..thank god fall is here....if anyone may know whats wrong...PLEASE PLEASE PLEASE reply!!

The ducts are switched by vacuum controlled "motors". It could be that one or more of them is not working or that a vacuum line is broken or has fallen off. If one has fallen off there would be a measureable vacuum leak.

The vacuum motors can be tested with a small hand-held vacuum pump. You may want to poke around under the dash with a flashlight and look for these motors. Cycle the A/C controls between all the different modes and you should see them move. You may find something is binding on one of their control arms.

The engine must be running for this as the engine produces the vacuum the motors use.

Good luck!
John

thank you John! Although this really means nothing to me- maybe it will to a mechanic! I have tried looking with a flashlight before under the dash...I don't remember being able to see a thing! This car has been a dream for me-has 138 k miles - nice body- and still going strong! <knocking on the nearest piece of wood available>....
I have never had a car last without tons of money going into it past 110k! now the headliner is another thing...... ;)
thanks again!