Geely EC718 2009 Workshop Manual page 252

2-170 Control System JL4G18-D
Step 5 Observe Pre-Catalytic oxygen sensor and Post-Catalytic oxygen sensor output voltages.
No
Warning!
Propane gas is a flammable gas. It is strictly prohibited to operate propane gas near a fire, otherwise it will cause a
fire.
Step 6 Test the oxygen sensor signal.
A
Step 7 Check whether there is exhaust leakage.
No
Replace the three-way catalytic converter. Refer to
Step 8
EC718/EC718RV EC715/EC715RV 10/2009
Whether Pre-Catalytic oxygen sensor and Post-Catalytic oxygen
sensor signal voltage is matching "Normal TWC" in the figure?
Intermittent Fault. Refer to
Yes
Fault Check
(a) If the voltage data is consistently below 0.45 V (mixture too
lean), carry out the steps as following:
• Spray proper amount of propane gas into the intake.
• Inspect whether the sensor voltage data changes
significantly, as the signal voltage will increase rapidly.
Pre-Catalytic Oxygen
Sensor Signal Voltage
Obvious Change No Change
No Change Obvious Change
Obvious Change No Change
No Change No Change
Replace the pre-catalytic oxygen sensor.
B
Refer to
Replacement. Go to step 11
Go to step 9
C
Check the cause for engine air-fuel ratio too
D
lean/too rich. Refer to
Table
Repair the faulty part. Go to step 11
Yes
2.7.6.2 Three-way Catalytic Converter
Go to step 11
Next
2.2.7.3 Intermittent
Post-Catalytic Oxygen
Sensor Signal Voltage
2.4.7.2 Pre-Catalytic Oxygen Sensor
2.2.7.4 Fault Symptom
Replacement.
Engine
To Step
A
B
C
D