94 ranger (4 cyl, manual) - no heat
#1
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great a/c, blower works fine, new thermostat, both htr core hoses are warm, BUT air blowing into truck cab is cold when temp is all the way warm and a/c is off.
Any HELP is GREATLY appreciated. I'm confused.
Thanks in advance
Any HELP is GREATLY appreciated. I'm confused.
Thanks in advance
#2
Problem with your mixing door. The system works by mixing the hot and cold air to give you the desired temp. The door opens one way for more warm air when you select that end of the temp range and vice versa for cold.
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94 ranger - no heat
towguy - when I slide the temp control to right/warm, the air flow changes out of the vent, but no heat, just cool. When I switch the a/c on - it blows cool even at the warm setting. AutoZone says its a 'blind lever door' and almost impossible to fix. Is that what you were referring to? Also checked and no heater control valve on this truck.
Thanks again
Thanks again
#5
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Most of todays vehicles work with a blend air door........and this vehicle may have one too. But it ALSO has a heater control valve on the right side of the engine.
FIRST...........make sure there is sufficient coolant to get TO the heater core. Then have someone turn the temp gauge from hot to cold and see if the arm on the valve moves.......Check for change of vacuum too........If the vacuum changes and the arm doesn't move it's a valve........if the vacuum remains the same check all vacuum hoses for cracks and breaks...........and the vacuum reserve ball
FIRST...........make sure there is sufficient coolant to get TO the heater core. Then have someone turn the temp gauge from hot to cold and see if the arm on the valve moves.......Check for change of vacuum too........If the vacuum changes and the arm doesn't move it's a valve........if the vacuum remains the same check all vacuum hoses for cracks and breaks...........and the vacuum reserve ball

#6
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the rangers did not have a water control valve. Check the cablec the are on the switch and make sure that they are moving the blend door(open the glove box all the way down to get a better view).
good luck
good luck
#7
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well I put my thinking hat on today. Remembered the guy I bought it from said it sat for almost 2 years. So I drove the truck around til it was warm, then felt the in and out heater hoses. In was warm; out was cool - so I just cut both hoses. They were almost dry inside, so I flushed the heater core with water from a hose. You cant believe the brown crud that poured out. Put nipple in both hoses and clamped, then started the engine - heat almost immediately. Hooray!!!
Thanks to all for the suggestions and advice.
Thanks to all for the suggestions and advice.

#8
If it really was that bad...I'll bet there is a new heater core in your future.......
Hope it lasts...really...I'm not being funny.
Hope it lasts...really...I'm not being funny.
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94 ranger - I GOT HEAT
I'll keep an eye on it. I checked on core - only about $30 and not too bad to change either. Do you think I should add some stop-leak as a precaution??
Thanks
Thanks