No Air from Dash Vents

[Mike W]

This is a minor issue - but air (hot, AC, vent) from fan has stopped coming through the dash vents. The fan, heat and AC all work and I can get fan air from the windshield (defrost) vents and at foot level. It's like the linkage to open up the dash vents isn't working. Any instructions, diagrams, or photos to help fix this? Mucho thanks!!

 

[stuntsunltd.]

Air from the vents

The first and easiest thing to check is a vacumn line. Open the hood and locate the Airconditoner components at the firewall. On top of these components you should find a small plastic vacumn line. this vacumn line supplies the vacumn to the inside of the truck where the air is switched from the defrost/floor or the vents. If the vacumn line is broke under the hood the vacumn pods (also refered to as a blend door) cannot function properly and will go to the defrost/floor setting you descride by default. If that line is intact then most likely the problem is one of the vacumn pods inside the dash has failed. You can test them by applying a vacumn to them. If you pull a vacumn on them they should move and stay in the new position until you release the vacumn. If they bleed off and return to their old position while vacumn is applied replace them.

 

[3rdCoastRanger]

I see this is an old thread. Is there any further information available on diagnosis and how to repair the problem? Thank you!

 

[3rdCoastRanger]

Some additional information: Vehicle is a 1997 Ford Ranger.

Problem:
The interior airflow (vent) selector dial is not controlling airflow direction. Regardless of where it is set, the airflow (AC, heat, or just vent) only comes out of the defroster vents.

History:
Starting a few weeks ago, I noticed that when at stoplights, the AC temperature would go up and the air would get musty, but while I was driving it cooled well. I also began to hear a new sound -- a very faint squeak or sigh when I would move the vent selector knob from "off" to AC. During this time the air (cooled by AC or heated) would flow from all vent positions properly. Now, regardless of where the dial is set, air only flows through the defrost vents.

Note: if the AC is on the air is chilled, if the heat is on the air is warm/hot, and in the mixed positions it is mixed, so the blend door is working properly. All flow is coming out through the defrost vents only.

Also, I so not think the mechanism activating the recirculating vs. outdoor air is working. When I move the AC dial to MAX AC the door allowing recirculating air should close and the noise level of the fan goes up significantly. that was the case a couple of weeks ago and now there is no change in fan sound when I move from AC to MAX AC.

I am hoping there is a clear diagnostic for the problem and a repair that I am able to make myself.

Thank you for your help!!