What else would cause a car not to have heat I have change the heater core and thermostat
Check both of the radiator hoses and both should be warm. If one is warmer than the other then issue lies in cooling system. Second, check the fuses. It could also be the switch that changes it from hot to cold. This can either be electronically controlled or vacuum controlled. There is a divider than switches from the AC to heater. Check the divider for movement.
common problems with the blend door
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