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Throttle Position Switch: Description and Operation


Throttle Valve Switch (Manual Trans.):





The Throttle Valve Switch is connected to the throttle valve shaft in the throttle body assembly and informs the ECM of throttle valve position. To differentiate between idle, intermediate and full throttle, the ECM detects resistance variations through the switch corresponding to these three throttle valve positions. This input is entered into various ECM calculations such as ignition timing, injector pulse width and air injection control.