Vacuum Switching Valve

Unit contains electromagnetic coil which is controlled by the computer or speed marker. When this coil is energized, valve is turned on, and vacuum advance is not allowed. On F engines, vacuum retards ignition timing. On 2T-C engines, vacuum switching valve also operates mixture control valve. Throttle positioner (not directly a part of T.C.S. system) is also controlled by vacuum switching valve.

Fig 1: SYSTEM SCHEMATIC (2T-C ENGINE)

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Fig 2: SYSTEM SCHEMATIC (4M ENGINE, CORONA MK II)

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Fig 3: SYSTEM SCHEMATIC (4M ENGINE, CROWN)

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