I have a 2003 Limited with dual zone electronic climate control.
For a couple years now, in the winter, this has been happening: The truck has been driven and is warm, blowing hot air. It is then parked until it is cold-soaked (i.e. overnight). When the truck is started, the heating system, which was running, blowing hot air when the truck was last shut off, wants to shut off because it is blowing cold air until the engine warms up. So when the truck is first started up, the heating system makes a kind of groaning noise for a second or so.
I can get it to make this noise as well if I switch it rapidly from heat to cold or back.
Click here:
Groaning sound made when temperature changed - opening and closing twice
This past summer, I noticed that my truck wasn't getting very cold when the A/C was on. My wife however, was freezing. Investigating, I discovered that changing the temperature of the heating system from low to high, the passenger side would change from blowing icy cold air to super hot air - while the driver's side would change from blowing warm air to warmer air. I can't get extreme temperatures out of the driver's side like I can out of the passenger side.
So...the question is, is this caused by a blend door actuator? A blend door? What's the most likely suspect? And how tough is it to fix?
This tutorial is for the manual heating system blend door actuator, but I'm pretty sure the dual-zone climate control will be different, as there will be two different blend doors (one for each side) - but I could be wrong about this.
My Haynes manual is less than worthless when it comes to this (no surprise there). So any help would be greatly appreciated.
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