Exhaust Gas Recirculation (EGR) System - Differential Pressure Feedback

The EGR System consists of an electric motor EGR valve integrated assembly, a MAP sensor, differential pressure feedback EGR sensor and PCM. Operation of the system is as follows:

Signals from the CHT sensor, TP sensors, CKP sensor and the MAP sensor provide information on engine operating conditions to the PCM. The engine must be warm, stable and running at a moderate load and RPM before the EGR system is activated. The PCM deactivates the EGR during idle, extended wide open throttle (WOT) or whenever a concern is detected in an EGR component or EGR required input. The PCM calculates the desired amount of EGR for a given set of engine operating conditions.

The intake manifold pressure is higher when the EGR is flowing than when it is not flowing. When the exhaust gas is delivered into the intake manifold, the MAP sensor reading increases.

The exhaust manifold provides a source of exhaust gas to the EGR orifice tube and the EGR valve.