Help!! Climate control stuck to default (defrost/floor)

[turbointhailand]

Alright... I am one of those people who hate when newcomers dont search the forums they are posting to... So just wanted to say that I have... Problem is with most of the old threads the links and photos are long gone.

So Here is the problem... My climate controls are stuck on defrost/floor mix... I have full control over air flow speed and temp, but I cant tell it where to go.

I have done some extensive searching of the forums and have determined that more than likely it is a vacuum leak, problem is I have yet to find any...

I checked the one that runs from the Drivers side firewall to the passenger side and to the glove box and it had a weak connection in the middle so I covered it in pvc tape and still its a no go...

Also checked the connection that runs from the passenger side firewall to or near the maf sensor (i think) and then to some metal canister near the bottom of the radiator and covered the weak spots with pvc tape as well...

So then I went and took out the climate control cluster above the stereo and all the connections looked fine and strong then I looked behind the glove box and the connections to the clear vacuum spliter thing (lol) seemed good too...

Hopefully someone can point me in the right direction... if you dont understand what part I was talking about I can take a picture... but if you have an Idea or a photo of what I should be looking for, I'd really appriciate it.

1993 2.3 LX Conv

 

[HISSIN50]

Did the check valve (along the passenger firewall) look ok? They crack.

If you have a mitivac, you could pull a vacuum on the line and try to hear where it's leaking.

I don't have pics or anything.

Good luck.

 

[Haus]

Check up in near/above the gas pedal if a yellow vacuum hose is disconnected from the canister. That is used to make the vents open when you select vents on your controls.

start here and then if not then go from there

 

[jrichker]

Somewhere I had a tech note with more help, but I can't find it at this time. Maybe the diagram will be useful...

Diagrams courtesy of Tmoss & Stang&2birds
HVAC vacuum diagram

 

[turbointhailand]

Did the check valve (along the passenger firewall) look ok? They crack.

If you have a mitivac, you could pull a vacuum on the line and try to hear where it's leaking.

I don't have pics or anything.

Good luck.

umm... whats the check valve look like?

 

[turbointhailand]

Check up in near/above the gas pedal if a yellow vacuum hose is disconnected from the canister. That is used to make the vents open when you select vents on your controls.

start here and then if not then go from there

Yep checked that one... here is a pic I snapped up there

and here is the rest of the pics I took of the vac lines and stuff yesterday...

Mustang pictures by this_beautiful_republic - Photobucket

 

[HISSIN50]

umm... whats the check valve look like?

You should have seen it when you traced the line along the firewall. It's just a black valve. If it broke, someone might have just put a connector in its place.

Edit: looks like it's there (could still be cracked though):
Top-left of the pic, just to the right of the passenger hood hinge. You can see a vac line going into what I think is your check valve.

http://s218.photobucket.com/albums/...lic/Mustang/?action=view&current=P1010903.jpg

 

[turbointhailand]

You should have seen it when you traced the line along the firewall. It's just a black valve. If it broke, someone might have just put a connector in its place.

Edit: looks like it's there (could still be cracked though):
Top-left of the pic, just to the right of the passenger hood hinge. You can see a vac line going into what I think is your check valve.

Mustang :: Vacuum Line picture by this_beautiful_republic - Photobucket

this?

 

[ID89GT]

Ya thats it, you will have a line goin to a vacuum canister inside the fender, and one going to the HVAC controls inside.

 

[95BEASTstang]

 

[turbointhailand]

what should I be checking these particular lines for...? cracks in the heads of th vac lines?

 

[ID89GT]

Check for any vacuum leaks at all, any vacuum loss in the HVAC lines will probably make it not work. I had a small crack in my vacuum line that goes inside the car just behind the dash by the firewall, and none of the controls would work till I fixed it.

 

[cardudeusa]

this?

Can these check valves go bad? My car recently started blowing out of the defrost/ floor only. I've replaced and inspected any lines under the hood and the dash as described above. I had a few of the hard plastic lines crack and brake which I replaced them with rubber vacuum line. I can't seem to find any leaks anywhere.

 

[Nevz86GT]

When this happened to me I found the problem to be the vacuum line that leads to the vacuum reservoir (black plastic ball) inside the passenger fender. I had to remove my inner fender (splash shield) to access.

 

[cardudeusa]

Oh wow sounds like fun! I'll have to check that. Thanks.

 

[Maaz]

Sorry for posting on this old thread but i need some help here... 2 days back my 2000 mustang's got stuck to defrost position... I chkd near the gas pedal and found two disconnected vacuum hoses... One red and one yellow... Now the issue is where do i put them... Please help me it is almost 50 degrees here

 

[jrichker]

Check out the diagram I posted above - 4th post from the beginning. It has the red and yellow vacuum lines and shows where they go.

Since you said 2000 Mustang, it may be slightly different. If it doesn't work, make your post in the 1999-2004 Mustang Forum.