GENERAL INFORMATION
(EGR SYSTEM)
The exhaust
gas recirculation (EGR) system lowers the nitrogen
oxide (NOx) emission level.
When the air/fuel mixture combustion
temperature is high, a large quantity of nitrogen
oxides (NOx) is generated in the combustion chamber.
Therefore, this
system recirculates part of emission gas from the exhaust port of the
cylinder head to the combustion chamber through the intake manifold to
decrease the air/fuel
mixture combustion temperature, resulting in reduction of NOx.
The
EGR flow rate is controlled by the EGR valve so as not to decrease the
driveability.
OPERATION
The EGR valve is being closed
and does not recirculate exhaust gases under one of the
following conditions.
Otherwise, the EGR valve is opened and
recirculates exhaust gases.
- The engine coolant temperature is low.
- The engine is at idle.
- The throttle valve is widely opened.
SYSTEM
DIAGRAM
