1998 Chrysler Grand Voyager not heating up

Is the problem cold air or no air flow?

If the thermostat were sticking open, the temperature gauge would also stay on cold. A radiator cap that doesn't maintain pressure could lead to an overheating condition. If the only symptom is cold air from the heater, suspect a plugged heater core. After the engine is warmed up, feel the two heater hoses. They should be too hot to hold onto for very long. If they're cool, the heater core should be back-flushed until water flows freely. If the hoses are hot, suspect a problem with the computer controls or an actuator motor.

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