Please help! Wind tunnel under dash

[faster340]

2004 xlt v6. Driving to work heat is fine despite busted blend door. (I opened glove box and jammed it open). Nice and quiet.

On the way home sounds like a wind tunnel under my dash and truck seems to be blown around a bit more on a windy night. Heat still working. Blend door doesn't seem to have any effect on this. Any insight on this?

 

[Number4]

The doors behind the glove box would be (right behind it) the fresh air/recirc air flap and (to the left near the stereo) the vent/defrost flap.

The blend door is controlled to the bottom left of the front console.

Where exactly did you jamb something?

 

[faster340]

I just took a piece of plastic and stuck it in the blend door that keeps going click click. Have the part but don't have time time. I will look further into it. Just wished it wasn't so damned cold.

 

[anthonymtz]

Gosh i feel you, I open my glove box and it's like a open window, air just comes right in... in not sure why, I haven't had any time to investigate lol.

 

[Number4]

Behind the glove box is the air intake exchange box. It has a flap. When you select anything but max air, the flap comes toward the passenger compartment creating a seal which only allows fresh air into the HVAC system.

When you choose max air, the flap goes toward the firewall and only allows air from inside the cabin to move through the HVAC system.

This flap breaks and usually falls to the bottom, covering the blower motor. At this point, if it falls flat, you will get what seems like setting one only on the blower speed. If it falls perpendicular to the blower, you'll maintain speed and not be the wiser.

In any case, you now have fresh air coming in unimpeded not only into the HVAC system, but directly into the cabin. Because the flap is no longer directing the fresh air.

 

[anthonymtz]

Behind the glove box is the air intake exchange box. It has a flap. When you select anything but max air, the flap comes toward the passenger compartment creating a seal which only allows fresh air into the HVAC system.

When you choose max air, the flap goes toward the firewall and only allows air from inside the cabin to move through the HVAC system.

This flap breaks and usually falls to the bottom, covering the blower motor. At this point, if it falls flat, you will get what seems like setting one only on the blower speed. If it falls perpendicular to the blower, you'll maintain speed and not be the wiser.

In any case, you now have fresh air coming in unimpeded not only into the HVAC system, but directly into the cabin. Because the flap is no longer directing the fresh air.

Wow, that is really interesting! Thanks for that info! I'll have to check that out this weekend and find out what happened to that flap.