in my 91 formy the ac wants to only blow out of thw defrost vents and not out the dash vents...it will eventually blow out the dash after a few minutes but its sorta weak most of the time and inst too cold....i took my dash off to see if i could see the "door" that is latched to the control lever for the a/c settings...but i couldnt see anything...but i looked directly in the middle vents w a flashlight and i saw a metal panel that looked like it may be a door of some type... so i moved the lever and it didnt move so i dont know if thats the right part im looking for or not....is this door that controls the air flow to the vents metal or plastic? thnx guys

we get this problem alot from other vehicles in our shop all the time. there is a door(s) like your talking about thats supposed to flip open and close to direct the airflow through out your AC duct. sounds to me like your door isnt opening to let the air through the vents. BUT it could be a number of things. Could be the vacuum isnt working to open the door or the motor (sorry cant remember if its electric controled or vacuum controlled on your year). It could be the door itself is just broke. It could even be the AC controls as well are just worn out over a period of time and wont let it switch over. The door your describing sounds like something totally different. Usually the flaps are made of plastic and you cant see em through your vents. I would suggest taking it by your local mechanic and try to find a decent price usually it dont cost that much to get it fixed. If you plan to do it yourself, be prepared it can be alotta work if your not sure on what your doing and sometimes can end up costing more in the end if you accidently break something in your dash. G'luck bud

here you go you've got a three way check valve that has formed a leak. they are usually under the hood on the passenger side near the ac dryer the big silver thing. look for three vacuum lines going to the same place cost about 3 bucks from the napa store and could be fixed by my 6 year old easy fix. hope this helps

okay...i looked and i didnt see 3 lines ...are the lines metal or rubber...i didnt see ANY rubber lines at all....im almost just so fed up w it cuzz it hasnt blown out the dash vents in 2 days!! and its startn to get on my nerves but it blows like a charm out of the defrost vent all day long...

It does kind of sound like a cracked vacuum check valve to me too. My 97 kept breaking them and it sould only blow out the defrost vent. On the 4th gens it is located next to the PCM (rear pass.side corner of the engine bay) connecting 3 rubber vacuum lines. Where it is on yours or if you even have one I'm not too sure.

i didnt see any rubber hoses..only metal lines...and i dont hear any hissing when i turn the fan to low then slide the lever so i dont think i have a leak or anything like that..im almost positive its the door inside the ducts becasue i dont hear anything opening or closing when i swith the lever over....