2008 GEELY CK fuel pump

70(3) Diagnosis procedure for insufficient engine power (Figure 150)
2. Poor deceleration
(1) Symptom
Idling is normal, but the engine is frequently turned off upon sudden release of the accelerator pedal
during driving.
(2) Causes and Troubleshooting:
a. Throttle position sensor is damaged and shall be replaced;
b. Initial idling is not properly adjusted or automatic idle control is wrong, fuel cut RPM is too low,
ECU fault, repair or replace them.Insufficient power
Insufficient
Check whether throttle valve can be fully open Unable to be fully open
Adjust

OK
Check whether the air cleaner is clogged Clogged
Clean or replace
OK
Check the throttle valve position sensor for failure Abnormal
Repair or replace
OK
Check the water temperature switch and thermostat NG
Replace
OK
Check the vacuum pressure sensor for failure NG
Replace
OK
Check the fuel pressure Excessively low or high
Service the electric fuel pump,
fuel filter and fuel pressure regulator
OK
Check the oxygen sensor Incorrect
Replace
OK
Check the injector Incorrect
Replace
OK
Replace the spark plug, ignition coil and high voltage wire
OK
Disassemble the engineFigure 150

713. Poor acceleration
(1) Symptom
Engine speed can not be increased immediately after depressing the accelerator pedal, there is time lag,and the acceleration reaction is delayed or there is slight fluctuation during the acceleration.(2) Causes and Troubleshooting
a. There is fault in throttle position sensor, repair or replace it;
b. Poor intake system seal, repair it;
c. There is low fuel pressure, troubleshoot it;
d. Poor injector operation, clean or replace it;
e. Intake pressure temperature sensor fault, repair or replace it;
f. Check valve is damaged and shall be replaced;
g. Ignition advance angle is not correct and shall be adjusted;
h. Fuel pressure regulator is damaged and shall be replaced;
i. Air cleaner is clogged and shall be cleaned or replaced;
(3) Diagnosis procedure for poor acceleration (Figure 151)
Figure 151Poor acceleration


Check the air tightness of the intake air system Poor seal
Repair

OK
Check whether the air cleaner is clogged Clogged
Clean or replace
OK
Check the throttle valve position sensor for failure Abnormal
Repair or replace
OK
Check the fuel pressure Abnormal
Service the electric fuel pump,
fuel filter and fuel pressure regulator
OK
Check whether the injector inject properly
at idle and maximum load NG

Replace
OK
Check whether the check valve and EVAP are faulty Yes
Repair or replace
OK
Check whether the vacuum pressure sensor is OK NG
Replace
OK
Adjust a ECU to retry

737. Unstable idle or engine shut off at hot status
(1) Symptom
Idle speed is normal during the cold start and becomes unstable at hot status, idle speed is too
low or engine is shut off.
(2) Causes and Troubleshooting
a. Idle is adjusted too low, adjust it to normal condition;
b. Water temperature sensor fault, repair or replace it;
c. Poor injector operation or big injection variation, repair or replace it;
d. Poor water temperature switch and thermostat operation, repair or replace it;
e. Check valve is damaged and needs to be replaced.
Figure 152Rough ildling, easy for engine shut off


Check whethe the air tightness of the intake system is good Poor
Troubleshooting

OK
Check idle control valve for operation Inoperative
Disassemble or replace
Operative
Reset the initial idle speed

Check the spark plug Poor
Adjust the clearance or replace
OK
Check the fuel pressure NG
Check the electric pump, fuel
pressure regulator and fuel filter
OK
Check the injector NG
Replace
OK
Check the pressure sensor NG
Replace
OK
Check the cylinder compression pressure NG
Disassemble the engine
OK
Check and adjust the valve clearance

7611. General engine fault symptom and faulty area (Table 7)
Table 7
Unable to explode initially
Unable to explode completely
Difficult for cold start
Difficult for hot start
No fast ilde
Low idle speed
High idle speed
Rough ildling
Idle hunting
At urgent acceleration
When the accelerator pedal is releasec
During idling
Poor acceleration
Hunting during driving
Insufficient power
KnockInta ke a bosolute pre ssure
se nsor
ccccccc cc
Water temperature sensorcccc cc c cc c
Re volution spee d se nsor
c
Throttle valve position
se nsor
ccc ccccc
Vehicle speed sensor
c
Fuel pump system
cc c cc c
Fue l pre ssure regulator
ccccc c cccc
Fue l filte r a nd pipe line
cc c cccc
Injector
ccccc c ccc
Sta rte r signal
cc
Ignition c oil
ccc
Spark plug
cccc c cc c
High pre ssure ca ble
cc
Ignition timing
cc c c c cc
Igniter in the ECU
c ccc
Throttle valve
cccc c
Throttle valve bodycc c
Air leakage in the intake
air systemcc ccccc c
Air valve
ccccc
ECU powe r supply circuit
c
Ignition swtich
c
Ma in re la y
c
Fuel pump re laycPoor driving Difficult to start Poor idling Engine off
Power
supply
system Control
system
Fuel
system
Ignitio n
system
Intake
air
systemSuspect
AreaSymptom

843. Output Level
ECU output level is designed to send control signal to the actuators of the electronic control system based on
the orders of the microprocessor in the micro-controller. The microprocessor control the output level by
controlling the occurrence position of the pulse, its length and duty ratio.
(1) Injection output level
The microprocessor controls the pulse length of the injection output level by making sure whether to
trigger to circuit or not in the injection output level.
(2) Ignition input level
The ignition output level is designed to amplify the ignition signal from the microprocessor into the primary
current of the ignition coil.
(3) Electric fuel pump output level
ECU microcontroller control the pump relay through electric fuel pump output level, and then control the
on and off of the electric fuel pump based on the current operating conditions.
(4) Other output levels
Control the output levels of the idle control valve, carbon canister solenoid valve, malfunction indicator
lamp. MR479Q, MR479QA, MR481QA engine idle control are closed loop control system, their injection
and ignition control are also closed loop control system.