Navistar International DT 466 Diagnostic/Troubleshooting Manual page 15

The VGT has actuated vanes in the turbine housing.
The vanes modify flow characteristics of exhaust
gases through the turbine housing. The benefit is the
ability to control boost pressure for various engine
speeds and load conditions. An additional benefit is
lower emissions.
An EGR control valve regulates cooled exhaust
gases entering the inlet air stream. Cool exhaust gas
increases engine tolerance for EGR, while reducing
smoke formed by gas dilution in the mixture. Three
EGR coolers are available depending on applications.
The water supply housing, which includes auxiliary
water connections, serves the dual function as the
Freon® compressor bracket.
Three control modules monitor and control the
electronic engine systems:
• Diamond Logic® engine controller – Electronic
Control Module (ECM)
• Injector Drive Module (IDM)
• Exhaust Gas Recirculation (EGR) drive module
Water In Fuel (WIF) separation occurs when the filter
element repels water molecules and water collects
at the bottom of the element cavity in the fuel filter
housing.
A Water In Fuel (WIF) sensor in the element cavity
of the fuel filter housing detects water. When enough
water accumulates in the element cavity, the WIF
sensor signal changes to the Electronic Control
Module (ECM). The ECM sends a message to
illuminate the amber water and fuel lamp, alerting the
operator. A fuel drain valve handle on the housing can
be opened to drain water from the fuel filter housing.
Optional Features
An air compressor is available for applications
requiring air brakes or air suspension.
A hydraulic power steering pump can be used with or
without an air compressor.
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
1 ENGINE SYSTEMS
The front cover includes a mounting flange for Power
Take Off (PTO) accessories. The air compressor drive
gear train, used with a spline adapter, provides power
for front mounted PTO accessories.
An optional Engine Fuel Pressure (EFP) sensor
detects low pressure caused by high fuel filter
restriction and sends a signal to the ECM; the ECM
illuminates the amber FUEL FILTER lamp on the
instrument panel.
The Diamond Logic® exhaust brake system uses only
the VGT to restrict exhaust flow for additional braking.
The operator controls the exhaust brake for different
operating conditions.
The Diamond Logic® engine brake is new for medium
range diesel engines.
system uses a high-pressure rail assembly and the
VGT for additional braking. The operator controls the
engine brake for different operating conditions.
The Inlet Air Heater (IAH) warms intake air entering
the cylinder head.
Options for vehicles and applications used in cold
climates include the following:
• Oil pan heater
The oil pan heater warms engine oil in the pan and
ensures oil flow to the injectors.
• Coolant heater
The coolant heater raises the temperature of
coolant surrounding the cylinders for improved
performance and fuel economy during start-up.
• Fuel heater
The fuel heater (a 300 watt element) in the base of
the fuel filter assembly heats the fuel for improved
performance.
EGES-270-1
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.
This compression braking
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