All settings on heater/ac/fan blow only through Defroster

[Jeep'nSon]

Hey guys,

turned on the heater the other day and air only came out through the defroster on top of dash. came to realize that it didn't matter what setting I used, the air only came out the defroster. Any thoughts or suggestions?

Thanks,
jason

[Rocky529]

You have a vacuum leak.. check the 'T' connection at the passenger side of the firewall and then follow the lines looking for the leak/crack.

[The Keith]

if it's disconnected from the manifold, you're cruise control won't work either. Mine keeps slipping off the nipple there...

[xulcuz]

Originally Posted by The Keith

if it's disconnected from the manifold, you're cruise control won't work either. Mine keeps slipping off the nipple there...

pics? This is exactly whats happening to me...

[Scotch740]

Originally Posted by xulcuz

pics? This is exactly whats happening to me...

This is on the driver's side of the engine.

[mike06X]

could also be the vacuum actuator arm broken; its a plastic part that snaps in, and they get brittle and break..take off the driver side knee kick panel, and look from the driver side at the middle of the airbox..engine running, move the selector from defrost to heat to vent and you will see the vacuum pod move, and i bet that you'l see the arm is just laying, not hooked up / broken off..

[Rocky529]

Originally Posted by mike06X

could also be the vacuum actuator arm broken; its a plastic part that snaps in, and they get brittle and break..take off the driver side knee kick panel, and look from the driver side at the middle of the airbox..engine running, move the selector from defrost to heat to vent and you will see the vacuum pod move, and i bet that you'l see the arm is just laying, not hooked up / broken off..

Not as common as you think it is.. I'd bet the vacuum leak.

[lashkk]

I have the same problem 97 SE with 2.5. Why would a vacuum leak cause your selector to not change the path of the air flow. Is the actuator arm contolled with a cable or a motor. Trying to fix mine as well. Is there a way to test and see if you have a vacuum leak?

[imjeepinVA]

I had the exact same thing on my 02, except for sometimes it would work properly and sometimes just air would come from the defroster.... The rubber boot that connects the 1/8" vacuum line to the vacuum reservoir under the battery, between the battery and the passenger side wheel well had a slit in it, causing a leak....

[Skyryder]

Originally Posted by lashkk

I have the same problem 97 SE with 2.5. Why would a vacuum leak cause your selector to not change the path of the air flow. Is the actuator arm contolled with a cable or a motor. Trying to fix mine as well. Is there a way to test and see if you have a vacuum leak?

These are vacuum controlled through canisters that when vacuum is applied pull a linkage arm that swings a lever connected to the deflector door. Just fixed mine yesterday. The lever that fits into a keyed slot pulled out and was dangling free. There have been other great write-ups on this, and the fixes. Being mine wasn't broke, just pulled out, I placed a drop of silicon on the end to help hold in place, , ,time will tell if it works, so far so good. My problem was the vent door, like where the A/C would blow, not sure but I believe that these little devils are interconnected some way as a couple of them have to move to get the desired result like defrost or floor etc.

Skyryder
'97 TJ

[xulcuz]

Originally Posted by scotch740

This is on the driver's side of the engine.

THANK YOU! I have been only having me heat on defrost all winter and it was really bothering me! Im a newb and never new that was even there but thank you again so much. The fitting was really really lose so Im gonna tighten it up tomarow! I just wish i would have discovered this before winter......

[Jeep'nSon]

Originally Posted by scotch740

This is on the driver's side of the engine.

I have to say thanks also, this was exactly my problem.

Thanks again.

Jason

[RickScott]

I am so glad I found this thread. My cruise and ventilation controls just went out and I'm sure this is what my problem is. I'll go check it at lunch. Thanks!
Rick

[randonlee25]

Originally Posted by Rocky529

You have a vacuum leak.. check the 'T' connection at the passenger side of the firewall and then follow the lines looking for the leak/crack.

A buddy of mine had the same problem! It's extremely easy to fix.

[sandmc]

My 97 SE is doing something similar. I have tried the remedy mentioned above but without success. One difference is that mine will change to blow from defrost to the feet, and sounds as though it is trying to switch to blow air to the face. Any ideas?