W150 1/2 Ton Pickup 4WD L6-225 3.7L VIN E 1-bbl (1982)
Air Injection Control Valve: Testing and Inspection
Air Switching Valve
Failure of the air switching valve is indicated when the valve receives a vacuum signal, but does not shut off air to the downstream injection point.
This valve is not serviceable and must be replaced if defective.