Throttle Full Open Switch: Description and Operation
Mounted on the throttle housing are switches for idle and full throttle positions. These signals are used to provide various fuel and ignition corrections during idle, deceleration, normal running, and full throttle operation.
The idle switch is closed when the throttle is closed, and opens when the throttle is moves about 1°. The switch signal determines the operation of the idle control valve, deceleration fuel shut-off, and the preset idle timing map.
The full throttle switch is activated at about 10° before full throttle. This signal is used to provide full throttle enrichment and to implement the full load timing map.