Engine/Transmission (1998.5 - 2002) HELP!! Heater Temperature Control

[Haney]

I need some quick help on trouble shooting my temperture control for the heater. I think I have my truck sold and the guy wants to drive it today. I noticed coming to work this morning that no matter where I put the temperture knob for the heater, it was WIDE OPEN. If I understand correctly, engine coolant is always being circulated throught the cab and the "blending" is done by a duct door???



Has anyone had this problem before? Is there a common problem with this control? Any help will be greatly appreciated. BTW, I had a rock come up and hit my windshield a couple weeks ago and I had it replaced. Could they have done this while replacing the windshield???? I have not driven it with the heat on since they replaced it.....



My truck is a 2001 24-v 5-speed SLT.



Thanks in advance... .

 

[sdalton]

I dont know if this applies, but, When I had a Jeep, the same thing happened to me. I thought it was something major. It turned out that a vacuum line had just come loose. It was a 5 second fix at the dealership. They didnt even write it up.