Grand Cherokee 4WD L6-242 4.0L VIN S MFI (1993)
Charge Temperature Sensor: Description and Operation
LOCATION
The Intake Air Temperature sensor is threaded into the intake manifold.
PURPOSE
The sensor element extends into the incoming airstream to measure the temperature of the air passing through the intake manifold.
OPERATION
The Powertrain Control Module (PCM) sends out a reference voltage of approximately five (5) volts to the coolant temperature sensor. As air
temperature changes, the internal resistance of the sensor will change, causing a varying voltage drop across the sensor. The PCM reads the
voltage drop across the sensor as charge air temperature.
The PCM uses this information to calculate the proper injector pulse width and spark advance.