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Throttle Position Sensor: Description and Operation

Idle (IDL) Switch:






PURPOSE
The Throttle Position (TP) sensor detects throttle plate opening angle and sends the ECA a signal indicating throttle position. The ECA uses this information to modify air/fuel mixture, idle speed, and fuel pressure.

OPERATION
Sensor produces 2 signals; one for idle (closed throttle) and the other for wide open throttle.

CONSTRUCTION
Consists of 2 switches sensing only closed or wide open throttle positions. These are referred to as the Idle (IDL) switch and Wide Open Throttle (WOT) switch.