D150 1/2 Ton Pickup 2WD V8-318 5.2L VIN R 4-bbl (1982)
Power Heat Control Valve: Testing and Inspection
1. Disconnect vacuum line from power heat control valve.
2. Connect a suitable vacuum gauge to the valve and apply 6 inches Hg to the valve. The valve should be fully closed. If valve is not fully closed,
replace valve.