How Do I Know If My Blend Door Actuator Is Bad?

How Do I Know If My Blend Door Actuator Is Bad? Knocking. Knocking sounds can almost always be attributed to a failing blend door actuator. … Clicking. … Any Other Strange Noises. … Inconsistent Airflow. … Inconsistent Temperature. … Wrong Temperature. What causes a blend door actuator to fail? Keep in mind that an obstruction