Geely Diagnosis Flow. Manual part — 2

5

No. 003 Over idle speed when warm-up

Malfunction Cause

Solution

Improper ignition time

Adjust ignition time

Incorrect fuel pressure

Check fuel pressure, whether the value is 265~304kPa. If it is
abnormal, shall check fuel pump and pressure controller, as well as
the balance fuel injection volume of each injector.

Throttle cable or inner
damper fails to return origin
position

If throttle cable or inner damper fails to return origin position, sc.
opening degree remains, shall check throttle cable and throttle.

Idle speed control valve or
stepping motor stuck

Check idle controller, whether there is over carbonization. Implement
clean and self-adaption value adjust when necessary.

Intake system leak

Check intake system, whether it is leaking. Maintain or replace when
necessary.

The sensitive resistance
temperature coefficient of
water temperature sensor
indicates inaccurately

Check water temperature sensor, at each temperature, whether the
operation resistance is in regulated range. For example, at 20 ± 1

℃

(temperature tolerance), the resistance shall be 2.27~2.73kΩ.

℃
Replace when necessary.

Exhaust gas oxygen sensor
malfunction

Check heater resistance of heated oxygen sensor (UAES 1~6Ω,
Delphi 12Ω, Polarsun 13.2±10%) , heater voltage (12V) and signal
voltage (0.1~0.9V), whether they are normal.
Check oxygen sensor, whether it is polluted or poisoned. When
oxygen senor outputs low voltage or signal error, then ECU will send
thick injection order, otherwise, replace the sensor.

A/C control signal error

Check A/C controlling system, whether it is normal.
Check pressure switch current, whether it is normal.
Check AC system pressure, whether it is normal.

Idle speed raised
when warm-up

ECU inner data unmatching

Check ECU, whether it is damaged. Replace ECU assembly when
necessary.

6

Over idle speed when warm-up

Water temperature sensor malfunction

Oxygen sensor malfunction

Intake system leaking

Idle speed control valve or stepping motor stuck

Incorrect fuel pressure

A/C control signal error

Improper ignition time (too early)

Throttle cable or damper malfunction

ECU inner malfunction

Normal

Normal

Normal

Normal

Normal

Normal

Normal

Normal

Abnormal

Abnormal

Abnormal

Abnormal

Abnormal

Stuck

Abnormal

Abnormal

Abnormal

Replace

Replace

Check

Check

Adjust

Check

Replace

Clean or replace

Maintain

7

No. 004 Idle speed fluctuation

Malfunction Cause

Solution

Throttle is stuck and

dirty

Clean and check throttle sealing condition.

Ignition maladjustment

Check spark plug, whether it is dirty, cracked or tracking;
Check wire of each cylinder, whether they are ageing, tracking, short or open circuit;
Check ignition timing, whether it is maladjustment. (ignition timing shall position at
10~12° before top dead center when idling. Adjust ignition timing advance angle if
necessary, when accelerating, the angle shall increase 20~30°)

Voltage unstable

Check battery voltage, whether the value is 12~14.5V;
Check generator, whether it operates normally;
Check body earth lead, whether it is fastened.

Sensor and executive

unit malfunction

Check cooling temperature sensor, whether the resistance is according with the
standard in different temperatures.
Check intake temperature sensor, and replace it when necessary.
Check idle speed control valve or stepping motor, whether it is stuck or damaged,
clean or replace it when necessary.
Check throttle position sensor, whether the bolts are over raised, and adjust them
when necessary.
Check oxygen sensor, whether it waves between 0.1V and 0.9V.
If injector sealing leaking, then replace injector assembly.
If spark plug operates poorly, then replace the plug.

Exhaust system

malfunction

Check canister, whether it is polluted and blocked.
Check exhaust pipe, whether it is deformed and damaged.
Check 3-way catalytic converter, whether it is damaged or blocked.

Poor tachometer

sensitivity

Check instrument connector, whether it is poor contact. Fix it again when necessary.
If it conducts normally, then replace the instrument panel.

ECU malfunction

Test the voltage between each 2 terminals of ECU, whether the value is in normal
range.
Check the connecting condition between ECU and wire.
Load data stream according to origin data.

Engine mechanical

malfunction

Check the pressure difference between each cylinder, whether they are over normal
range.
Check the sealing condition of each cylinder.

8

Idle speed fluctuation

Throttle is stuck and dirty

Ignition maladjustment

Exhaust system malfunction

Voltage unstable

Sensor and executive unit malfunction

ECU malfunction

Engine mechanical malfunction

Normal

Normal

Normal

Normal

Normal

Normal

Abnormal

Abnormal

Abnormal

Abnormal

Abnormal

Abnormal

Stuck, dirty

Clean

Adjust

Check or replace

Check

Replace

Check or replace

Replace