Mechanics

HEATER IS NOT BLOWING HOT AIR

1992 Mazda MPV

Heater problem
1992 Mazda MPV V6 Two Wheel Drive Automatic 143000 miles

when I turn the heater on it does not blow hot, only very little warmth. Asking you before I start messing with anything.
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Howard cashen
December 1, 2007.




Try warming the Vehicle, then carefully feel the heater hoses, are they both hot? If one is cooler than the other, You need to flush the core, or a replacement job on the heater core. Also if the system has a heat control valve on the heater hose, make sure it is working!
Or Blend door
Let's say for the sake of arguement, the core is ok, which just because it was blown out, may have worked, then it's possible that the temperature blend door is stuck. The shaft it swings on is metal, and over time they tend to rust and binde up, operated the temp knob while you look for or feel for the actuator that moves that door, some actuators ar vacuum operated, some electrical. Either these motors, called servo motors can go bad or the above mentioned issue! If the shaft is frozen, try a small drill bit at the base of the shaft, drill thru the plastic and spray some white lithium grease in there, if you can move it by hand, so much the better! Work it back and forth till it moves freely!

Merlin2021
Dec 1, 2007.


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