Maintenance Manual for J2 Sedan
Electronic Control System
of Engine
238
Trouble phenomenon 12: Slow response of acceleration
General trouble position:
1.
Poor quality of fuel; 2. Intake pressure sensor and air throttle position sensor; 3.Spark plug;
4 .Throttle body and idle bypass air passage; 5.Intake passage; 6.Idle adjustor; 7.Fuel injector;
8.Ignition timing; 9. Exhaust pipe
General diagnosis procedure:
No.
Operating Steps
Detection Results
Subsequent Steps
Yes
Repair air intake
system
1
Check air filter for blockage.
No
Next step
Yes
Next step
2
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 when idling is at
about 260kPa. disconnect vacuum hose from pressure
regulator to see whether fuel pressure is about 300kPa.
No
Repair fuel supply
system
Yes
Next step
3
Check the spark plug of each cylinder to observe whether its
model and gap are in compliance with the specification.
No
Adjust or replace
Yes
Wash related
components
4
Dismantle the idle adjustor to check whether there is carbon
deposit in the air throttle body, idle adjustor and idle bypass
air passage.
No
Next step
Yes
Next step
5
Check whether the intake pressure sensor, air throttle position
sensor and its circuit are normal.
No
Repair circuit or
replace sensor
Yes
Failure of replacement
6
Dismantle the fuel injector and check whether there is
leakage or blockage in the fuel injector with cleaning
analyzer special for fuel injector.
No
Next step
Yes
Change fuel
7
Check fuel condition and observe whether the trouble
phenomenon occurs just after adding the fuel.
No
Next step
Yes
Next step
8
Check whether the ignition sequence of engine and ignition
timing is in line with the specification.
No
Repair ignition timing
9
Check whether the operation of the exhaust pipe is smooth.
No
Repair or replace the
exhaust pipe
Yes
Diagnosis help
10
Turn on the ignition switch and check whether the power
supply and earthing are normal.
No
Repair related circuit
