GENERAL INFORMATION (EXHAUST GAS RECIRCULATION SYSTEM)
The exhaust gas recirculation 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 inlet manifold to
decrease the air/fuel mixture combustion temperature, resulting in
reduction of NOx.
The exhaust gas recirculation flow rate is
controlled by the exhaust gas recirculation valve so as not to decrease
the driveability.
OPERATION
The exhaust gas recirculation
valve is being closed and does not recirculate exhaust gases under one
of the following conditions.
Otherwise, the exhaust gas recirculation
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