No air from dash vents. I searched but still have a question

[trents99]

After searching posts on this I went and checked all my vacuum connections and everything seemed to be fine except one. On the passenger side vacuum tree there is a line that runs from the vacuum tree into the firewall right where the condeneser lines go. That hose seems to have possibly come loose to whatever it connects to behind the firewall. I can push and pull it rather freely. So how do I get to this? Do I take the cowl panel section off?

 

[Henceforward]

When my vents didn't work, I checked the hoses under the dash, on that little 4 pin vac tree. One of them was not connected, so I hooked it up, and 5 years of leaves, dust and ***** came out of the foam trap door whn it opened up.

Just check the hoses under the dash first, remove the glove box, and find it, then check while the engine is running, to see if they have suction.

Might check the AC controls, to see if the hoses are on there also.

 

[trents99]

Are you talking about the tree behind the glove box? I checked those but I'll double check. I read that the connections on back of the controls are bolted in so it would be unlikely that they would come out. I'll double chek to be sure though.

The door on the bottom, under the glove box, I opened it and it is clear of debris. Is that door ever supposed to open based on what setting the controls are put on?

 

[drillgod2000]

when my vents didn't work, it turned out to be one of the vac lines going to the smog pump.

 

[trents99]

when my vents didn't work, it turned out to be one of the vac lines going to the smog pump.

Huh that's weird. The vac line to my smog pump got burned in half not long ago when it was touching the header. Never thought that would cause it because I just plugged the line. I have the smog pump by-passed too.

 

[txstang84]

i think he's got a point there, i believe all those lines run from the same vacuum source, but i'd be more inclined to try henceforwards theory, i had the same problem several years ago, turned out to be one disconnected line under the dash. those stupid little vinyl lines also crack pretty easy, so ck all of them over really well

and yes that trap door opens when you have the a/c on "max" also known to many as recirculate, it pulls air from the floor and recirculates the cooler air over the evap core.

 

[trents99]

Ok I just went and checked and here's what I got.

Lines under/behind dash checked out okay. Pulled controls to check the ones on the back and they were fine. Previous owner had for some reason zip tied the arm from the vac canister behind the glove box that controls the flap door to a piece of the dash. I cut that zip tie but still not working.

In the engine compartment on the passenger side. The smog pump line has a vacuum fitting on top. There is nothing going to it. That's the one that got burned in half. The side that runs to the vacuum tree is plugged. Also on that tree there is a white hose. That one is plugged. There is a hose coming out of the passenger side fender well next to the firewall that wasn't hooked up. I hooked it up to a broken line that was coming off the tree mounted on the firewall. All this and it still doesn't work. What I could use is some pictures of how everything is hooked up correctly. I've looked at diagrams and they aren't much help.

 

[txstang84]

ok, the one coming out of the passenger side fenderwell is for a vacuum ball (reservoir) the line coming out by the evap core should be hooked to a little tri-hose tree mounted to the firewall directly above the evap core (right above the two brake lines that run from left to right on the firewall "shelf") one hose should go to the big vacuum tree above your brake booster, the other...i can't remember where it goes-i had to heat pinch mine since all my emissions equipment has been gone since I got the car. that's how mine's hooked up, and the vents all work as advertised...

that's all i think of at the moment

 

[trents99]

Okay that's how mine is. The one that goes into the firewall by the evap lines, that's where I think the problem is. When I push/pull on it there doesn't seem to be anything connected to it behind the firewall. It just feels loose.

 

[txstang84]

ugh...umm, can you dig around behind the blower fan/ac box assembly and locate the part of the line coming in? it shouldn't wiggle around all that much, that line may've come disconnected at the junction or broken under your dash-you could always put a vacuum hand pump to it and see if it's got any resistance

 

[PuterAmI]

On your driver's side firewall is the source tree. This has one marked A/C. This is where the source line for your cabin controls start. It goes across the firewall as a hard plastic line. It goes to the tee where one side goes to the reservoir (for times you are at WOT and you still need vacuum), and the other goes into the cabin. First, verify that you have vacuum to the tee. The hard plastic line usually gets a crack that you cannot see and leaks. Next, pull the source line from the tee and draw a vacuum, either with a pump or your mouth. See if it holds. Also pull the line to your reservoir and see if it holds. These sometimes crack and you cannot see it.

You will find your problem this way.

The smog vacuum has nothing to do with the cabin controls on a Fox.

 

[txstang84]

i think he already visually ck'd all those lines under the hood..(?)

 

[trents99]

Yeah I did a visual but there may be a hairline I am missing. I grabbed one line off the passenger side tee and it crumbled in my hand. The lines are all messed up so I'm just going to go buy new ones.

The one that goes into the firewall by the evap lines. I can't get to it from in the car. I have a bad feeling the dash will have to come out to get to it.