Exhaust Gas Recirculation (Egr) System; General Information; Operation; System Diagram - Mitsubishi Electric Lancer Evolution-VII Workshop Manual

ENGINE AND EMISSION CONTROL -

EXHAUST GAS RECIRCULATION (EGR) SYSTEM

GENERAL INFORMATION

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

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.

SYSTEM DIAGRAM

Throttle body
Emission Control System
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.
The engine coolant temperature is low.
D
The engine is at idle.
D
The throttle valve is widely opened.
D
EGR control
solenoid valve
ON
EGR valve
Engine
control
relay
Battery
Engine-ECU
Air flow sensor
Engine coolant
temperature sensor
Crank angle sensor
Throttle position sensor
17-13