why does my heater blow cold air
A couple of things, is the temperature gage running in the normal range? No change from where it was? If so, thermostat would need to be replaced. Then there is the AC actuator module up under the dash that may be bad, It controls the vent system in the dash, part of it being the outside air blend door (flap, whatever) that controls the temperature inside the cabin. Other than that, may need a coolant flush as radiator and heater core may be plugged a bit.
I don't no what to do
I have the same problem with my '06 Silverado which has dual temperature zones. It only blows cold air intermittently and only on one side. Any ideas?
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