[RLD831]

I am having a problem where no matter which setting my vent selection knob is set to, most of the air blows out of the defroster. Some will blow out of the foot vent, and even less will blow out of the face vents. I know this is usually caused by a vacuum leak, but my cruise control works perfect still. I had it on constantly for a 3 hour trip about a week ago.

Could the door itself be stuck open? How would I go about checking it? Could my system be leaking enough to cause the vent selector to stop working, yet still allow my cruise to engage?

 

[SpeedJeep]

There are several vacuum lines connected to the back of your HVAC controls. That is where you need to check for leaks.

 

[RLD831]

If my problem is with the defroster always blowing air, would that mean that the leak is in the yellow hose? I checked all of the vacuum actuators. They work, but the defroster actuator is very slow.

 

[danielbuck]

any update on this? I'm having a similar problem, the vent selector used to be a bit slow to actually change, now it won't change to all of the vent settings, it'll only (slowly) change to a few of them. The fan speed still works very well though, as does the temperature. I'll check my vaccum lines and see what they are doing

 

[badtux]

I had this problem, the solution ended up being a vacuum hose under the hood near the cruise control vacuum ball that I somehow knocked loose while running power wires for my ham and CB radios. So look for stray hoses under there, that may be your problem too.

 

[danielbuck]

so I finally got around to checking the hoses, after a few minutes I then realized that it was the actual knob itself that was broken! If I turn the metal piece behind the knob with some pliers, it works perfectly. LOL Well I'm glad it's not some hose that I have to chase down, I'll just turn it with some pliers for now (if I ever even need to turn it, I don't run the AC, only the heat when it's cooler out) until I can get a new knob, haha!

 

[JEGS25]

I had this problem on my 1999 TJ too, the blower was only blowing out of the defroster. Turned out to be a really easy fix, simply a broken vacuum line. run through all of the lines to check for leaks. The one that needed a repair on mine was very accessible and took about $2 and 15 minutes to fix (#3 on the diagram).

Hopefully your fix is this easy.

 

[kendle.jeremy]

I had this problem on my 1999 TJ too, the blower was only blowing out of the defroster. Turned out to be a really easy fix, simply a broken vacuum line. run through all of the lines to check for leaks. The one that needed a repair on mine was very accessible and took about $2 and 15 minutes to fix (#3 on the diagram).

Hopefully your fix is this easy.

This diagram made the process so easy!! Thank you so much!!