Air/Fuel Mixture: Testing and Inspection

IDLE MIXTURE CHECK
1. Before inspection, set the vehicle in the following condition.
^ Engine coolant temperature: 80 - 95°C (176 - 203°F)
^ Lights, electric cooling fan and all accessories: OFF
^ Transaxle: Neutral (P range on vehicles with A/T)
2. Turn the ignition switch off and connect the scan tool to the data link connector.
3. Check that the basic ignition timing is within the standard value.
Standard value: 5° BTDC ± 3°
4. Run the engine at 2,500 r/min for 2 minutes.
5. Set the CO/HC tester.
6. Check the CO contents and the HC contents at idle.
Standard value:
CO contents: 0.5 % or less
HC contents: 100 ppm or less
7. If the CO and HC contents do not remain inside the standard value, check the following items:
^ Diagnostic output
^ Closed-loop control (When the closed-loop control is carried out normally, the output signal of the heated oxygen sensor repeats between 0 - 400 mV and 600 - 1,000 mV at idle.)
^ Fuel pressure
^ Injector
^ Ignition coil, spark plug cable, spark plug
^ EGR system and the EGR valve leak
^ Evaporative emission control system
^ Compression pressure

NOTE: Replace the three-way catalyst whenever the CO and HC contents do not remain inside the standard value. (even though the result of the inspection is normal on all items).