2004 expedition Eddie Bauer Front AC blower is on but nothing coming through 4 dash vents

[Whalin]

Hey all. My Expedition front AC blower has me scratching my head. It runs and from the sound of it runs really good. But cold air is only coming out of the 2 halls dollar side vents a top the dash, 1 each side. The 4 vents in the face of the dash stew getting no air passing through them. I’ve checked the vents and the doors open and close perfectly fine and each one is manual open/close so nothing like a door actuator or anything to go bad. The 2nd and 3rd room seating head liner vents (2 for each row) are of course using the rear blower and and their own controls. I thought at first maybe the main rear controls that are up front in the head liner near the rear view mirror may be conflicting with the front blower controls or what not. But every configuration, deflation or addition of controls, fuses/relays are giving me nothing at all to go on in terms as why the front is on and works, pushes air through the 2 small vents on top the dash but not the 4 main dash ones. Lol
I haven’t been able to find anything helpful in regards to this but maybe I hadn’t expanded my efforts enough or even may not hand looked at the right articles/info. Thanks everyone, any help is perfect cause at this point…. I’m about to run new ac lines from the rear blower up front cause daaaayuum, that rear blower pumps the air out pretty damn fast

 

[Hamfisted]

Check vacuum line going into the firewall just below the PCM . If there's no vacuum to the control solenoid under the dash the front vent control won't work properly.


Make sure the vacuum line is attached to the hot water valve....





Vacuum supply line firewall pass-thru grommet ....sheathed line is from hot water valve, unsheathed line is supply line from intake manifold ....






.

 

[cecilbridge]

Check the vacuum line carefully it’s likely broken. You might have to remove the battery & battery tray to get more room to work. Please note the vacuum line also supply vacuum to the 4x4 switch and there is a one way valve on the line. Make sure the 4x4 is NOT engaging if the line is broken when the engine is ON and it’s in 2H .. Jack the front wheels up and spin the wheel. It should turn freely without the axle turning when the engine is OFF and When the engine is ON in 2H

 

[GaryH]

If the floor vents are still pushing air, look for broken/deteriorated vacuum hose at the firewall right behind the battery. You will probably have to remove the battery to see it.