MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES
104
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
leakage or blockage of the fuel
system
system.
Fuel injector
Bad performance or blockage of
the fuel injector
Replace
the
fuel
injector.
Whenever the fuel injector is
replaced, it is required to input
the 13C code of the new fuel
injector into the ECU again.
Overlow pressure for injection
and opening of the fuel injector
Check the high pressure fuel rail
pressure or replace the fuel
injector.
Bad control of fuel injection
Repair it after diagnosis, input
the newly composed 13C code of
the repaired fuel injector into the
ECU.
Fuel injector circuit
Breakage of the fuel injector
circuit
Check, repair or replace wire.
Looseness of the injector circuit
Fasten the fuel injector circuit.
High pressure fuel rail pressure
sensor, high pressure oil rail
pressure adjusting system
Damage of the high pressure
fuel rail pressure sensor
Replace the high pressure fuel
rail pressure sensor.
High pressure fuel rail pressure
adjusting system
Check the metering valve and
the oil return valve, replace the
damaged parts.
Mechanical part of the diesel
engine
Damage of the cylinder gasket,
gluing
of
the
piston
ring,
excessive wear of the piston ring
Check or replace the cylinder
gasket and the piston ring.
13. Diesel Engine Running at a High Idle Speed
Checking Item and Part
Cause of Malfunction
Troubleshooting
Pedal position sensor
Damage of the pedal position
sensor
Replace
the
pedal
position
sensor and calibrate the ECU.
14. Starter not Working, Lacking Power, and Making noise
Phenomenon and Cause of Malfunction
Troubleshooting
Starter not
working
(1) Disconnection of the control
circuit such as the starter switch
(2) Bad contact between the carbon
brush and the commutator
(3) Open circuit or short circuit in the
starter
(1) Check whether the circuit is firmly connected.
(2) Adjust the carbon brush spring pressure and
clean the commutator.
(3) Overhaul the starter.
(continued)
