under the hood on the left center near the inside firewall is a hose that has a small open and close valve on it. It kind of looks like a pin that slides into the side of the hose. Clean it and spray a little wd40 on it. The switch somtimes gets road junk built up on it. Mine works great now. you may have to open the motor compartment to get to it from the inside of the van. Not sure, my '89 van does the same thing. I am going to look at the cable from the heat control knob to the heat box, maybe the door isn't opening up. If it is opening like it should, then the heater core my be plugged up. This would require removing and cleaning or replacing the heater core. Also a cooling system flush now is good. Any help on how to remove the heater core?
check you antifreze level if it is low you wont have eat or if you get lots of fog your heater core is bad
The a/c - heater controller is out...........
You need to back flush the heater core have had to do it to my jimmy 2 times and fixed the problem is easy fix .
Under the dash near the firewall. Good Luck!
You have a broken vacuum hose under the hood that supplies the switch.
hi im having the same promble and im starting to thing its the thermostat im going to change my send me your email address i tell u if that work t.picard@ hotmail.com
Under the right side of the dash board, under the air ducts
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