Exhaust Gas Recirculation (Egr) System - International VT 365 Service Manual

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The VGT is a closed loop system that uses the
Exhaust Back Pressure (EBP) sensor to provide
feedback to the ECM. The ECM uses the EBP sensor
to continuously monitor EBP and adjust the duty cycle
to the VGT to match engine requirements.
VGT control
Figure 16 VGT control
The solenoid receives a pulse width modulated signal
from the ECM that indicates the on / off time that the
control valve is energized. The control valve directs
lube oil flow to both sides of the piston in the actuator
housing. Directing oil to different sides of the piston
increases or decreases exhaust back pressure.
Actuated vanes are mounted around the inside
circumference of the turbine housing. A unison ring
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
ENGINE SYSTEMS
links all the vanes. When the unison ring moves,
all vanes move to the same position. Unison ring
movement occurs when either side of the actuator
piston is pressurized by engine oil.
Exhaust gas flow can be regulated depending on
required exhaust back pressure for engine speed and
load.

Exhaust Gas Recirculation (EGR) System

The EGR system includes the following:
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The Exhaust Gas Recirculation (EGR) system
reduces Nitrogen Oxide (NOx) emissions.
NO
oxygen at high temperature during combustion.
Combustion starts when fuel is injected into the
cylinder before or slightly after the piston reaches
top-dead-center.
EGR flow
Some exhaust from the right exhaust tube assembly
flows into the EGR cooler. Exhaust from the EGR
cooler flows into a passage in the air intake manifold
that intersects with the EGR valve.
When EGR is commanded, the EGR control valve
opens allowing cooled exhaust gases to enter the
intake manifold to be mixed with filtered intake air
then recycled through the combustion process.
EGES295-2
Follow all warnings, cautions, and notes.
© 2006 International Truck and Engine Corporation
EGR drive module
EGR valve
EGR cooler
Air intake manifold
Exhaust tube assembly, right
forms during a reaction between nitrogen and
X