Idle Speed Vacuum Solenoid Valve: Description and Operation

Fig. 22 TP System Operations Schematic:

Fig. 23 TP System Operations Chart:

The Throttle Positioner diaphragm is controlled by a VSV, which is opened and closed by the ECU. The ECU senses engine rpm on deceleration and controls the throttle valve return rate to idle position. The VSV inputs the ECU through terminal TP.