Climate control diagram for '91?

[Yo]

I tried searching and found a few items, but mostly pertaining to the AC system.

Anyway, I noticed yesterday when I was driving away that my heat did something weird; I went to switch from floor to vent and it made a strange clunk, almost like something fell in there or dislodged.

Anyway, heat at vents only flows ab 50% now relative to fan speed. I can hear the air escaping under the dash, and if I put my hand underneath I can feel hot air escaping somewhere....

Defrost, floor, and all AC functions work perfectly. AC at the vents blows hard, but when I switch to heat, it seems like the flapper's not closing all the way.

I'm not sure where to start, does anyone have any suggestions or a diagram?

 

[dhcomp]

Diagram isn't really needed. Get under there and start looking. The heater/ac box is under teh passenger side dash, you can look for heater core replacement instructions to find removal instructions. I suggest you take it all apart, and you'll see what blend doors are working, and which are broken. Also, you will see how the center lower duct connects, and can determine if there is huge gaps in teh connections. My guess is that they aren't connected anymore.

Basically, don't be afraid to start tracing duct, and see what things look like when you start disassembling.

 

[Yo]

Makes sense. Thanks for the reply!

 

[dhcomp]

When i put mine together, i ended up with about 1/2 gap in the lower duct feed and the defrost duct feed. I used duct tape (correct purpose for once.....haha), and tried to seal it as best as i could. Way better than it was before.

 

[Yo]

Well I bought the replacement foam surrounds for the right side driver and center vents, but I haven't put them in yet.

I have a roll of the same stuff, but it's narrower. It's just so strange that the vents would just fart out like they did.

Maybe I'm crazy, but the sound I heard when I swapped back to the vents from the floor yesterday was similar to something falling in, like a drill bit or something.

Maybe something was on the cusp of falling in for a long time coming now and is preventing the flapper from closing all the way.

 

[dhcomp]

Well I bought the replacement foam surrounds for the right side driver and center vents, but I haven't put them in yet.

I have a roll of the same stuff, but it's narrower. It's just so strange that the vents would just fart out like they did.

Maybe I'm crazy, but the sound I heard when I swapped back to the vents from the floor yesterday was similar to something falling in, like a drill bit or something.

Maybe something was on the cusp of falling in for a long time coming now and is preventing the flapper from closing all the way.

The vac pot rod to flapper door connection broke on mine on a few of teh doors. I ended up getting a whole heater/air box from a wrecked truck, cause i knew it had a brand new heater core in it, and i needed to replace my core