Geely Diagnosis Flow. Manual part — 14

53

Canister valve failure

Oxygen sensor failure

Engine bracket cracked

Low fuel pressure

Intake temperature sensor failure

Exhaust system blocked

Injector failure

Voltage abnormal

Intake pipe leak

Individual cylinder fails to work

Electric controlling system failure

Idle speed control valve or stepping motor failure

Idle speed by-pass pipe blocked

Improper throttle position sensor adjustment

Idle speed unstable

Clean

Check

Check

Clean and replace

Replace

Replace

Replace

Replace

Replace

Check and replace

Check

Check

Clean and replace

Adjust and replace

Low

Cracked

Fail

Abnormal

Abnormal

Abnormal

Blocked

Abnormal

Abnormal

Abnormal

Improper adjusted

Blocked

Fails to work

Leak

Normal

Normal

Normal

Normal

Normal

Normal

Normal

Normal

Normal

Normal

Normal

Normal

Normal

54

No. 031 Non-idle speed

Malfunction Cause

Solution

Idle speed air pipe blocked

Check throttle and idle speed air pipe, whether they are blocked. Clean
them if there is too much carbon deposit to ensure free-flowing intake.

Ilde speed stepping motor
malfunction

Check idle speed stepping motor, whether it operates normally and flexibly.
Clean it if there is too much carbon deposit. Replace motor when
necessary.

Loose throttle pedal and check throttle cable condition, adjust it if the
clearance is improper.

Improper throttle cable or
thorttle position sensor
adjustment

When throttle is closed totally, inspect throttle position sensor idle speed
switch, by Geely special decoder, whether it operates normally. Adjust or
replace it when necessary.

Electric controlling system
malfunction

Connect Geely special decoder to check whether there is malfunction code.
And inspect again if it shows malfunction code. Then check relevant
component and circuit according to the indication of malfunction code.

Cooling fluid temperature
sensor malfunction

Check cooling fluid temperature sensor. In different temperatures, the
resistance of coolant temperature sensor shall vary according to regulated
standard. Otherwise, replace it.

Indicidual cylinder fails to
work

Check operating condition of each cylinder, whether individual cylinder
operates abnormally, particularly inspect the spark plug, spark wire and
cylinder pressure etc. Maintain or replace relating parts when malfunction
cause was found.

Engine voltage abnormal

Check running engine, whether the output voltage of generator is in normal
value. If it is abnormal and results unstable idle speed, then check
generator and relating circuit and parts. Maintain or replace them when
necessary.

Intake system leaking

According to idle speed operating principle, vacuum pipe leaking will result
non-idle speed. Shall replace vacuum pipe.

Incorrect engine valve
timing

Timing belt loose and cause gear malposition, as well as similar condition
with non-idle speed. Shall adjust ignition timing.

Circuit malfunction

Part of idle speed controlling circuit is ageing or affected by water, may
result non-idle speed. Shall maintain circuit.

Non-idle speed,
engine shut-off
when pressing
throttle pedal

Engine ECU malfunction

Pull out ECU engine connector, measure the resistance between each
terminal by multimeter, whether the value is corresponding to technical
requirements. Replace engine ECU when abnormal.

55

Engine ECU failure

Circuit failure

Incorrect engine valve timing

Intake system leaking

Engine voltage abnormal

Indicidual cylinder fails to work

Cooling fluid temperature sensor failure

Electric controlling system failure

Improper throttle cable or thorttle position sensor adjustment

Ilde speed stepping motor failure

Idle speed air pipe blocked

Non-idle speed

Check

Check

Clean and replace

Replace

Replace

Check and adjust

Check

Check

Check

Clean and replace

Clean

Leak

Error

Fails to work

Abnormal

Abnormal

Abnormal

Abnormal

Abnormal

Abnormal

Abnormal

Blocked

Normal

Normal

Normal

Normal

Normal

Normal

Normal

Normal

Normal

Normal

56

No. 032 Idle speed over normal value

Malfunction Cause

Solution

Improper throttle cable or throttle position
sensor adjustment

Loose throttle pedal and check throttle cable condition.
Adjust it when the clearance is improper.

Throttle contains too much carbon deposit,
sc. it is stuck, which results the throttle fails
to close normally.

Check throttle, if there is too much carbon deposit, which
results throttle fails to close as normal, then shall clean it.

Idle speed stepping motor malfunction

Check idle speed stepping motor, whether it operates
flexibly. If it is stuck, caused by carbon deposit, and then
shall clean it. Replace stepping motor when necessary.

Intake system leaking

Intake pipe leaking, result incorrect decision to air flow
rate on ECU, and causes improper control, which leads
to over idle speed. Check leaking position, particularly
the intake manifold gasket, fuel injector seal ring,
vacuum pipe and connector etc.

Electric controlling system malfunction

Connect Geely special decoder to check whether there
is malfunction code. And inspect again if it shows
malfunction code. Then check relevant component and
circuit according to the indication of malfunction code.

Cooling fluid temperature sensor

malfunction

Check water temperature sensor, whether it can send
temperature signal to ECU correctly. In normal condition,
the coolant temperature is applied to adjust fuel injecting
quantity, sc. mixture gas viscosity. In low temperature,
ECU controls injector to inject more fuel to increase
mixture gas viscosity, as well as idle speed. Check water
temperature sensor, if it fails to measure temperature as
normal. In different temperatures, the resistance of
cooling temperature sensor shall vary according to
regulated standard. Otherwise, replace coolant
temperature sensor.

Intake pressure sensor malfunction

Check intake manifold pressure temperature sensor,
replace it when abnormal.

Oxygen sensor malfunction

Measure oxygen sensor, if the voltage is low, beneath
0.5V, then will cause incorrect ECU order, which results
mixture gas viscosity increase, as well as idle speed.
Replace oxygen sensor when necessary.

Idle speed over
normal value

Engine ECU malfunction

Pull out engine ECU pin and measure the resistance
between each terminal of ECU, whether the value is
accordance with technical requirements. Replace engine
ECU when abnormal.