Now that I've got an accurate reading on the outside temperatures, I need help with another HVAC problem. My heat and A/C both blow hot and cold respectively, but i'm noticing that it's only coming out of the defroster vent(s) on the very top of the dash against the windshield. I'm told that there could be a vacuum line messed up that it not activating the servo or whatever controls the doors that change the airflow direction. Where would I look for this? Any help would be hugely appreciated because it sucks when the A/C is on but you can barely feel it because it's coming out of the farthest possible vents.

It's the CJ2 unit, the fully digital 2-zone one, if that's important.

Yes, it's a vacuum modulated unit and is a HUGE PITA to change if it is in fact the unit.

but where is it and where is the vacuum line that goes to it so I can at least check that first?

i'm still looking to find a picture for you.

My friends g/f GTP is having this same issue and I don't think they are fixing it just because of the location...

There's a vacuum/electric solenoid under the dash on the passenger side, to the right of the blower motor case. Check the vacuum line there for leaks.

do i have to take out the glove box or anything? or just stick my head under there?

Take off the gray panel below the glove box, it's held on with push pins.

ok, im gonna go outside and do that now

I would check the ignition switch. The contacts inside mine got covered in carbon and caused basically the same thing to happen.

Blackarrow, I didn't see any leaks in the vacuum lines under the dash. Am gonna look again later to double check.

Nemo, not sure how it would be the ignition switch when everything else that runs off of it is fine. Also, the A/C still blows cold air, but it's coming out of the wrong vents at times.

An update though, It seems that on the setting where the arrow points at the man's face on the CJ2 unit, about 60ish% of the air comes out of those (correct) vents, but the rest splits between the defroster vents and the feet. On any other setting however, it comes almost entirely out of the defrost vents, with a trickle coming out at the feet. Even on the one where it's supposed to be half feet and half middle vents, most of the air comes out at the defrost. Anyone got any other ideas as to why this would occur?

As always, thanks in advance for any help.

So I'm trying to bump this and get any other answers i can get. any help is appreciated.

From my description in my previous post, is it possible that something is blocking the doors inside the dash from moving? Also, if someone could point me to a link on how to remove part of the dash and where to look to find this possible obstruction, that would be great.

Once again, any help at all would be appreciated.

Have you checked the climate control unit for stored codes? Click this link for more info: http://www.grandprix.net/ubb/ultimatebb.php?ubb=get_topic;f=1;t=004227;p=1#000009 (Scroll down)

I tried this, the only code was 104 (historic ambient sensor circuit open). I know this is because i has ran the car briefly with no sensor plugged in before I got the new one. It's not showing any other codes.

If you can't find any vacuum leaks, you can try cleaning the ignition switch first. If that doesn't fix it, it's time to get out the digital multimeter, and start checking the wiring harness between the solenoid and climate control unit.

Would the ignition switch really cause it? I'm not having any trouble with anything else that runs off it. Also, the doors inside are moving because when i go to change it from the middle vents to the upper or lower, it does change, but it seems to be only changing to the upper defrost vents. I don't want to sound like I'm arguing with your opinion, but I'm just not sure that it could be the problem, unless you know something that I dont about the way these systems work?

So today, for ha-has, i decided to take out the glove box assembly and see what I could see. All the vacuum lines/wires appear to be in good condition. Also, without the box there, I can clearly hear the solenoid/modulator making noise whenever i push the "mode" button on the cj2 unit to change where the airflow is going. However, even after i push the button to shut the A/C off, it continues the noise for a good 15 second or so. It sounds almost like it is trying to change the direction of whatever doors move the airflow, but it's not able to do it.

My question would be this then: Is there any way to take off at least part of the dash and see this (these?) doors? Where should i be looking for this? Also, does the term "blend door" refer to this item, or is that something else entirely?

What you are describing is the diverter. That directs where the air goes. The blend doors control the temperature. There are three diverters, 2 on the passenger side and one on the drivers side. I'm having the same problem. I'll check it out in a couple of days when I get back in town.

Derek

I hope you realize that it's pretty much just me that checks in on these pages, and that this thread died in 2009. The rest of the site died a couple of years later. Thank you for joining, but you're damn near a decade late to the party. While the participation in these hallowed halls is scarce, the information is still around. Again, welcome...and good luck.