AC/Defrost wierd sound, what is it?

[treepete]

When I switch from floor heater to defrost mode and back sometimes I have to crank up the fan speed for it to switch over... if that makes sense. Its like a flapper valve needs the extra oomph of the fan to help it switch over to blowing out of the defrost vents, anyone else have this or know the part Im talking about? Im going to have the dash out this weekend I think, and as long as Im in there, i thought I could look for this and fix it etc.

and while im at it, my 3 year old has put quite a bit of money into my ride... literally.
my change in the console is all gone.... gone down the vent next to the radio.
I hear it jingle in there when I hit bumps and stuff... but where can I go to get it out? I think it slid waaay in there cause I cant see it when I look with a flashlight. any ideas on that?

 

[tspain]

I'm trying to come up with something to help you out. I'm looking over some schematics and I'll post back when I find something.

It sounds like you have a mode door sticking, or a mode door actuator that is weak.

I'll post back.....

 

[treepete]

Yeha, right on that would be great. If this mode door actuator is weak, that sounds like a solid diagnosis based on the sound it makes. If you please, tell me or maybe a drawing or something of where this actuator is located?
thanks again for your help.
Pete

 

[tspain]

1. Disconnect the negative battery cable.

2. Disconnect the electrical connector to the mode actuator that is located on the left side of the air distribution case.

3. Remove the screws.

4. Remove the adjuster links from the control lever.

5. Remove the mode actuator.

6. Adjust the mode actuator by completing the following steps:

6.1. Connect the electrical connector to the actuator.

6.2. Turn the ignition switch to the RUN position.

Allow the self-positioning of the actuator.

6.3. Turn the ignition switch to the OFF position.

6.4. Remove the actuator from the electrical connection.

Installation is reverse of removal.

© 2008 General Motors Corporation. All rights reserved.

 

[tspain]

Ok, I spoke with another tech about this. He said it could be a weak actuator, or more than likely, the mode door is sticking from drinks spilled down the center vent, by the cupholder, or from some of the change.

You can clean the door by going in from the floor vents with a rag soaked with warm water, and try and clean up the door edges, then try and spray some silicone lube on the door seals.

 

[treepete]

awesome. I forgot to say thanks for this. sorry its 6 months late.