TC BY Maserati V6-181 2972cc 3.0L SOHC VIN S FI (1991)
Distance Sensor: Description and Operation
Vehicle Speed Sensor (VSS)
This sensor is located in the extension housing of the transaxle, and it generates 8 voltage pulses for every revolution of the axle shaft. These pulses are
sent directly to the Single Board Engine Controller (SBEC). The SBEC uses these signals along with the signals from the Throttle Position Sensor
(TPS) to determine a closed throttle deceleration condition or a closed throttle idle (vehicle stopped) condition.
Under idle (vehicle stopped) conditions, the SBEC sees that there are no signals being generated from the vehicle distance (speed) sensor, and it adjusts
the Automatic Idle Speed (AIS) motor to maintain a desired engine idle speed. Under closed throttle deceleration, the SBEC receives signals from the
vehicle distance (speed) sensor, because the vehicle is still moving, and it adjusts the AIS motor to maintain a desired Manifold Absolute Pressure
(MAP) sensor value.