Heater blowing hot on one side 2004 Sport

[Amorica]

Hi everyone:

All of a sudden the heat, no matter what setting is blowing hot only on the drivers side. The passenger side is cool. I have played with the heater settings to see if it was just stuck, but no luck. Has anyone else had this problem or have any clue as to what is going on?

Please help!

Thanks.
Rob

 

[tommyk]

heat on d/s only

IT could be two things that come to my mind for this problem plugged heater core or blend door not working.

 

[iBison]

If you have dual climate control it could be the controls, happened in my grand prix.

 

[gimmea250swb]

I'm reviving this one since I don't have 15 posts yet.

2004 Limited. Driver heat is good, but the farther right you go the cooler it gets. If you switch to defrost, it's cold air. I pulled the glovebox door and both servos seem to be working fine. Thermostat seems to work fine too. Upon startup, the water lines are compressed and after heating up, they expand and become warm. My guess is the heater core, but why does only one vent work if the heater core is clogged?