Air Coming Out All Vents

[JMT]

Like the title says, air blows out all my vents when I turn the air on. I replaced the blend door actuator, no change. The blower works fine. It’s an 05’. Anyone have this problem before? Suggestions?

 

[OHFIVETJ]

If i recall correctly, I think it was a vacuum issue ............or lack of ?

 

[qslim]

The FSM has a pretty good section (at least my '99 does) on the vacuum system, it helped me find a couple of cracked lines that were intermittently leaking last year and making my HVAC all goofy.

Edit: That's actually not true lol. I used the FSM to find all the vacuum lines, understand how they actuate the blend doors, then I got frustrated looking for a little vacuum leak on a 20 year old Jeep so I just went to Napa and got about ten feet of vacuum hose and changed them all. That fixed it.

 

[JMT]

The FSM has a pretty good section (at least my '99 does) on the vacuum system, it helped me find a couple of cracked lines that were intermittently leaking last year and making my HVAC all goofy.

Edit: That's actually not true lol. I used the FSM to find all the vacuum lines, understand how they actuate the blend doors, then I got frustrated looking for a little vacuum leak on a 20 year old Jeep so I just went to Napa and got about ten feet of vacuum hose and changed them all. That fixed it.

Was this your problem or something else goofy? Thank you

 

[qslim]

Was this your problem or something else goofy? Thank you

Mine was just erratic - sometimes It would change to the dial setting, sometimes it wouldn't, sometimes it would default to the front dash vents or the defrost. I put a vacuum pump on the actuators, they seemed to respond normally to vacuum. The FSM has a pretty detailed procedure on how to check the vacuum switching valve at the knob, but I never did that test. I figured my 20 year old vacuum lines could use replacing anyway, especially the ones in the engine bay.

 

[dbbd1]

With all of this "stay at home" stuff, is your jeep just sitting there? Sometimes, it's rodents chewing through the vacuum lines in the winter as they make nests, but now, maybe it's just convenient for them.

 

[JMT]

Mine was just erratic - sometimes It would change to the dial setting, sometimes it wouldn't, sometimes it would default to the front dash vents or the defrost. I put a vacuum pump on the actuators, they seemed to respond normally to vacuum. The FSM has a pretty detailed procedure on how to check the vacuum switching valve at the knob, but I never did that test. I figured my 20 year old vacuum lines could use replacing anyway, especially the ones in the engine bay.

So the FSM it is. Why do I always forget to go there first?!

 

[k-huevo]

Look at the vacuum hose under the battery box to see if it has been pulled off/out.

 

[JMT]

With all of this "stay at home" stuff, is your jeep just sitting there? Sometimes, it's rodents chewing through the vacuum lines in the winter as they make nests, but now, maybe it's just convenient for them.

I’m still driving It here and there. It’s been doing this for five months!

 

[JMT]

Look at the vacuum hose under the battery box to see if it has been pulled off/out.

I’ll check that! Thank you. This is driving me crazy

 

[OHFIVETJ]

Good informative video below:

VACUUM:



BLEND DOOR:

 

[MackDog]

Hey Guys, many greetings from Germany. Could you tell me what the "FSM is?
many thanks

 

[Chris]

Hey Guys, many greetings from Germany. Could you tell me what the "FSM is?
many thanks

Jeep Wrangler TJ Factory Service Manuals (FSM) & Technical Documentation

 

[JMT]

Hey Guys, many greetings from Germany. Could you tell me what the "FSM is?
many thanks

Factory Service Manual