EGR Temperature Sensor: Description and Operation

PURPOSE
The EGR gas temperature sensor is used for on-board monitoring of EGR valve operation.

OPERATION
EGR operation is controlled by the engine control module (ECM). By measuring temperature on the intake manifold side of the EGR passage, the ECM is able to determine whether the EGR is actually opening when the EGR control vacuum switching valve (VSV) is energized. If proper EGR operation is not detected, the ECM illuminates the Malfunction Indicator Light (MIL) and sets trouble a code (DTC 71).