Navistar International DT 466 Diagnostic/Troubleshooting Manual page 258

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NOTE: When using the EST to do KOEO or KOER
diagnostic tests, Standard Test is always selected
and run first. If the ignition switch is not cycled, the
Standard Test does not have to be run again.
4. From the KOER Diagnostics menu, select Low
Duty cycle from VGT Tests, and select Run to start
test:
Use the suggested toggle sequence below, to
check turbocharger operation from one duty cycle
to the other.
• Low to medium
• Medium to high
• High to low
• Low to high
To toggle between duty cycles, select one of the
two remaining duty cycles and select Run to start.
As the VGT duty cycle increases when toggled
through the low, medium, and high duty cycles,
the EBP and MAP values should increase in
relationship to the VGT duty cycle. Conversely,
when duty cycle is reduced, there should be a
reduction to the EBP and MAP values.
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
6 PERFORMANCE DIAGNOSTICS
5. Record results on Diagnostics Form.
Possible Causes
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EGES-270-1
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.
If the ECM does not receive a request from
the EST, after about 40 seconds, the test will
automatically end and the engine will return to
normal operation.
• Did EBP and MAP change for each transition?
— If yes, continue to the next diagnostic test.
— If no, turbocharger is suspect for low
power condition.
(Turbocharger Assembly and Actuator)"
in Section 4.
Intake or exhaust leaks
Intake or exhaust restrictions
Plugged EBP tube assembly
Biased MAP or EBP sensor
Failed VGT actuator
Failed turbocharger
Failed EGR control valve
See "Low Power