Climate Control Problems

I have a 2001 Intrigue. I am having a problem with the climate control. No matter what the drivers side tempature is set to the passanger always blows the same tempature air... Any ideas?

I ended up joining alldata.com and found out that there is an electric motor that opens and closes the air door to control the tempature. I thought this was vacuum controled. Anyway I called the dealer and they wanted almost $200 for the part so I went to a salvage yard and they gave it to me for $40. It was not hard to get off. Hope this helps someone