What should be partially removed from the valve before removing a tire for repair?

The valve core should be partially removed before removing a tire for repair because it is the component that controls the airflow in and out of the tire. By partially removing the valve core, you allow the air to escape from the tire, which is necessary to safely and effectively remove the tire from the rim. This helps to prevent issues such as tire blowouts or damage during removal.

The valve cap is simply a protective cover that prevents dirt and debris from entering the valve and does not affect the tire removal process. The pressure gauge is a tool used to measure tire pressure and does not need to be removed to facilitate tire repair. The air filter is unrelated to tire maintenance, as it generally pertains to engine or air conditioning systems, not tires.