MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES
114
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
2. Turbocharging System Malfunction Diagnosis
Malfunction diagnosis:
①
The malfunction diagnosis means to find out the position and cause of the
turbocharging system malfunction and clear the malfunction accordingly.
②
Don’t replace the
turbocharger before clearing the malfunction.
③
The malfunction diagnosis method and procedure for
the turbocharged engine are the same as those of the non-turbocharged engine.
④
The malfunction
diagnosis cannot be conducted after the turbocharger is removed.
Diagnosis phenomenon
Malfunction diagnosis for the turbocharged engine
In
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Possible cause
Troubleshooting
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Dirty air cleaner
Replace the filter core of
the air cleaner
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Blockage in the
compressor air intake
pipe
Clear the foreign matters
or replace the broken
components accordingly.
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Blockage in the
compressor exhaust
pipe
Clear the foreign matters
or replace the broken
components accordingly.
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Blockage in the engine
air intake pipe
Clear the foreign matters
in the air intake pipe.
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Air leakage from the pipe
connecting the air
cleaner and the
compressor
Replace the sealer or
tighten the fastener to
the required torque
accordingly.
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Air leakage from the pipe
connecting the
compressor and the
engine air intake pipe
Replace the sealer or
tighten the fastener to
the required torque
accordingly.
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Air leakage from the
junction surface between
the engine air intake pipe
and the cylinder head
Replace the gasket or
tighten the fastener to
the required torque
accordingly.
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Blockage in the engine
exhaust pipe
Clear the foreign matters
in the exhaust pipe.
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Blockage in the silencer
or the exhaust pipe
behind
Clear the foreign matters
in the exhaust pipe or
replace the broken
components accordingly.
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Air leakage from the
junction surface between
Replace the gasket or
tighten the fastener to
