GENERAL INFORMATION (EGR SYSTEM)
The electronically controlled EGR system consists of an EGR
valve, engine-ECU and sensors.
The EGR valve aims at reducing the
amount of NOx (nitric oxide) discharge that increases with the rise in
the exhaust gas temperature. Also, the EGR cooler bypass system is
employed. By blocking the exhaust gas flow not to pass through the EGR
cooler at the engine cold state, HC (hydrocarbon) emissions are reduced.
Thus, the engine-ECU optimally controls the exhaust gas temperature in
accordance with the operating conditions of the engine.
To further
improve the exhaust gas reduction performance, the system provides the
engine-ECU feedback on the EGR valve opening. Thus, it effects EGR
control to optimize the operating conditions of the engine.
SYSTEM DIAGRAM