Hey guys, so I'm helping my aunt with her 2002 Monte Carlo. When the cold air is being used cool air comes out the passenger side and hot air comes out the drivers side. Any ideas what could be causing it?

 

Sounds like the slider may have came off track or broke.
There are threads here to remove it.

 

Freon could also be getting low. If that's the case though, the passenger side will stop blowing cold soon also. That's the problem in my car. I think it's the compressor leaking. I'm going to splurge and have it fixed in the spring.