Vehicle Speed Sensor

On vehicles equipped with M/T, Vehicle Speed Sensor (VSS) generates 4 pulses per sensor revolution. VSS input is used by Engine control module to determine vehicle speed and distance traveled.

Speed and distance inputs along with TP sensor closed throttle input, determine if a closed throttle deceleration or normal throttle idle (vehicle stopped) condition exists. During deceleration, ECM controls IAC motor to maintain a desired MAP value. During idle (vehicle stopped), ECM controls IAC motor to maintain a desired idle speed.