Thanks for the help. Face vent setting doesn't work on my '01 in all phases and temps. All 4 levels of the fan work and the other settings work. Is this a control **** issue, or a resistor, blend door? Just saw posts in 3rd gen.... Thanks much.

A/C defrost and foot control is great in 95 F weather, but I like the face vent.

 

Check for a loose/disconnected vacuum line near the brake booster.



Did you just change the fuel filter?

 

I did recently change the fuel filter. Haven't had much call to use the vents until the last week or so though. I'll check it out and post. Thanks.

 

Vaccuum lines appear to be okay, but now the foot setting doesn't work either. I was hearing the door or whatnot move when I was selecting foot or defrost etc, but now I'm not.

 

I will check more vaccuum lines when I get home, saw this online.

http://www.justanswer.com/questions/...am-2500-deisel

except my CC seems to work fine.

 

If thats the case and the other vacuum lines in the picture that shovelhead posted are OK then check the small black plastic vacuum line that goes through the firewall at the AC fittings, thats the one that runs all the dash vent doors but not the blend door. It might be that actual actuator though as you say all other modes work OK?

 

I've lost the foot vent too now but have all 4 speeds and temp control. Thanks.

 

Temp control is electric and fan speed is not related, so it sounds like a vacuum problem. If your cruise and 4X4 work then check that little black vacuum line by the AC fittings on pax side firewall

 

Maybe the leak is in the cab, because I don't see another way after checking. Thanks for the help.

 

Over on the drivers side by the hump is a vacuum connector block. All the vacuum lines that run the vent and recirc doors are in that block. The black line is the supply. Maybe it's come apart. The only other vacuum connector is on the back of the rotary selector sw in the dash. Just literally pull the bezel out in one piece then remove the screws holding the three switches in. I don't think it would be that though.

 

I had a similar issue a couple of yrs back. Turned out to be my brake booster. My vent would shut when I held the brake but come back after I was off of it for a while.
May not be your plroblem but it's worth looking into. Unplug the line to the booster and put a plug in it, if that doesn't fix it you can probably rule it out.

 

The search continues, can move the "actuators" and make the vents work, all hoses in that white connector block are attached, so it would have to be at the switch, wouldn't it? I double checked everything under the hood all the way to the firewall.

 

Check to see if the lines have cracked anywhere.
I've had vacuum lines that look fine, and the only way to see if a lengthwise crack is there, is to twist the lines themselves. Or, you can test to see if vacuum exists at the ends of the lines. Start with the supply on the connector. You should be able to feel vacuum with your finger, or a smooth piece of flat plastic. I have heard of the heater control cracking/breaking internally, and causing your problem. I had my vacuum line fall across my intake manifold and melt...leaving me with defrost only.

 

Do you have vacuum at the short black vacuum line connector coming out the firewall by the AC fittings under the hood? My guess is NO. If you DO, then the problem is inside, if not then the vacuum supply is at fault, which is most often the case.

 

I haven't been able to do anymore as of right now, still at work, will check it as soon as I get home. I was going to ask if it were possible for one side of that pump to die and not the other. I will triple check those external lines but pretty sure they're not cracked. Need to pull the bezel too.

Wife was dying to get out of the house when I got home... will check points right to left under the hood during warmup tomorrow morning.