Exhaust Gas Recirculation: Description and Operation

Function

Vehicles with engine code ALH
Activation of Exhaust Gas Recirculation (EGR) system occurs from Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- via EGR Vacuum Regulator Solenoid Valve -N18- to EGR valve. The mechanical EGR valve with cone-shaped valve plunger makes different opening diameters possible at different valve lift. Every relevant valve position is possible via cyclic activation.

Vehicles with engine code BEW
Activation of EGR system occurs from Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- via EGR Vacuum Regulator Solenoid Valve -N18- with Potentiometer for EGR -G212-.

NOTE:
- Always replace self-locking nuts.
- Engine Control Module (ECM) is equipped with On Board Diagnostic (OBD).
- Components marked with * are tested via On Board Diagnostic (OBD), Diagnostic mode 3: Check DTC memory.