JAC J2 User Manual

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
Maintenance Manual for J2 Sedan
Electronic Control System
of Engine
229
Trouble phenomenon 3: Difficulty in warm start
General trouble position:
1.
Poor
quality of fuel; 2.Fuel injection
pump;
3.Coolant te
mperature
sensor;
4.Igniti
on
coil
General diagnosis procedure:
No.
Operating Steps
Detection
Results
Subsequent Steps
Yes
Next
step
1
Connect the fuel pressure gauge (the access point is
at the front end
of the induction manifold of the fuel
distribution pipe assembly) to
the engine and start the engine
to check whether the reading of fuel
pressure gauge at idle
condition is at about 260kPa. Disconnect
vacuum hose on pressure regulator and observe whether fuel
pressure is about
300kPa.
No
Repair fuel supply
system
Yes
Next
step
2
Pull out the high-voltage wire
of one of the cylinders and connect
the spark plug to make the
spark plug electrodes about 5mm away
from the engine body, and start the engine
to check whether there is
the blue and white high-voltage spark.
No
Repair ignition system
Yes
Repair circuit or
replace the sensor
3
Pull out connector of coolant temperature sensor and start the
engine to observe whether the engine is successfully started at this
time. (Alternatively, connect a 300 ohm resistance in series at the
connector of coolant temperature sensor to observe whether
the
engine is successfully started at this time.)
No
Next step
Yes
Repair
or
replace
4
Check the vacuum pipe of fuel
pressure regulator for the shedding
or air leakage.
No
Next step
Yes
Change
fuel
5
Check fuel conditions and observe w
hether the trouble phenomenon
occurs just after adding fuel.
No
Next step
Yes
Diagnosis
help
6
Turn on the ignition switch and check whether the power supply
and earthing are normal.
No
Repair related
circuit

JAC J2 Specifications

General

Brand	JAC
Model	J2
Category	Automobile
Language	English