rasouth
Well-Known Member
- Joined
- July 29, 2015
- Messages
- 345
- Reaction score
- 49
- City, State
- Riverside, CA
- Year, Model & Trim Level
- 96 Explorer XLT 4.0 OHV
Hi everyone! Happy Holidays! I have a '96 4.0 that is blowing hot air through the vents. This started suddenly just a few days ago. I usually have my dash settings on vent, cool, upper and lower vents. I live in SoCal so I don't use heat too often. When I have my temp set to cool, vent only (no a/c) I have noticed that my a/c compressor will kick on. (Not the problem here). The problem in question is, should the heater control valve (that has two hoses going into the firewall) be closed to stop hot coolant from circulating in the heater core when temp is set to cool? The heater control valve seems to work as in if I apply vacuum to it the plunger/valve moves upward, shutting off coolant. If I have vent only blowing hot air and then apply vacuum to heater control valve, no more hot air. (Gray vacuum line leak, maybe?) If I turn a/c on then I get cold air with mixing with the hot air. (Possible blend door?) I'm leaning towards the vacuum leak because if I apply vacuum to valve everything works as it should. By the way... Where does the gray vacuum line go after it leaves the heater valve and disappears under a/c condenser? Mine seems to go behind the inner fender well.