OK,, winter is coming now and I really should get that heating fixed and I need some advice before I take things apart. The only thing that comes out of the vents is cold air no matter what the settings. Also there is a constant clicking noise thats coming from the air control area. No traces of rad fluid in the car. Also when I got the car those 6 months ago, there was a hose disconnected from a fluid distributor thingy (with two plugs red and green) near the winshield wiper fliud tank, there should be a pic under my user name. Nothing was leaking from it though,, and my coolent level was good. I connected it back right away (still no heat),, not sure if that has anything to do with it but anyway what should be done to fix it?
Your problem could be one many things. Do you have a TRSM? If not, you need to try to get one or at least a copy of the AC section. It is fairly easy to trouble shoot the system and find the defective part or parts. The part on the firewall that was disconnected is the Water valve. It controlls the heated water moving through the system. More than likely you have an open in the system causing it to blow only cold air.
I'd search a bit more... The clicking thread I remember had somthing to do with needing to use contact cleaner on the tempreture selector. I don't think that will fix your heating though. (By all means correct me if I'm wrong...) The heating systems on MKII's extensively use engine vacuume as a "Motive" force to open, close and regulate air and water flow into the cabin. The "fluid distributor thingy" uses vacuume from the dash control to regulate hot water flow. By appling vacuume (Suck on it!)to the little nipple on the top you can force the valve wide open. Do your heater hoses change temperature when you do this? eg. cold before...hot after?
If you remove this hose while the engine is warmed up with the temperature selector is on full heat and rev the engin a bit you shoud feel suction on this hose. If not somthing is stoping the vacuume flow. At that point check the easy stuff. Is any vacuume being supplied to the entire dash control? The vacuume supply is from a tee in the line on the top of the firewall that also supplies the cruise control. Sorry I can't post a picture. Mine ended up being a disconected hose but ... you might not be so lucky. If the dash is being supplied vacuume and is still not working you probably need a TSRM manual to start testing each component seperatly ect. Good luck... You will need it!
I looked at the car today, and I noticed something strange about that hose (hose in my pic). It was connected staight to a pipe in the firewall, when I looked at my Haynes repair manual in the picture it looks like its connected to the eng block. But I'm not sure,, the manual doesn't tell me much about the heater core,,, and by the way "82MKIILtype" it wasn't the small hose that was disconnected it was the big one. I'm begining to think that the hoses have been switched around by the old owner. Also the solar sensor has a cap and appears to be fine, still clicking though... WHATS WRONG HERE?
O.K. Sounds to me like the previous owner disabled the heater by taking the heater core out of the coolant loop. Usually this is done because the core has a leak so you don't get a puddle of coolant inside the dash and floor. A.K.A THE CHEAP FIX. Others do it to try to limmit the possibilities of where coolant could be leaking out if they are trying to find a stuborn leak.
The arrow in your picture should be connected to to back of the head dead center between the cam towers. the hose that comes out of the bottom of the water valve then goes into the firewall. The coolant then loops through the heater core ... and back out of the firewall. From there I think it connects to the back of the engine block down near the bottom. (it might even loop around the back of the block and attach into the bottom of the thermstat housing ...I Forget)
If your heater core is going to leak you will get foggy mist on your windshield ... you may hear gurgleing sounds ... a stink like you've never smelt before ... and possibly a puddle of coolant on your nice clean interior carpet. I have never had to change a core in a Supra but I have changed one in a 84 Celica ... shit man ... good luck! It is NOT a fun job. If you happen to have a friend who moonlights as a midgit contortionist who can stand on his head for over an hour NOW would be a good time to ask for help.