T100 Pickup 4WD V6-180.5 2959cc 3.0L SOHC (3VZ-E) (1993)
Vacuum Switching Valve: Description and Operation
PURPOSE
The Pulsed Secondary Air Injection (PAIR) Vacuum Switching Valve (VSV) is used to control vacuum applied to the Pulsed Secondary Air
Injection Valve as determined by the Engine Control Module (ECM).
OPERATION
During normal driving conditions with low coolant temperatures the ECM activates the VSV and allows vacuum to be applied to the Pulsed
Secondary Air Injection Valve. This action also occurs on deceleration at normal operating coolant temperatures when the throttle plate is closed
at certain RPM's.