Air/Fuel Mixture: Testing and Inspection

1. Before inspection, set vehicles 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 to 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. Start the engine and run it 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 it is not within the standard value, check the following items:
- Diagnosis output
- Closed-loop control (When the closed-loop control is carried out normally, the output signal of the heated oxygen sensor changes between 0 - 400 mV and 600 - 1,000 mV at idle.)
- Fuel pressures
- Injector
- Ignition coil, spark plug cable, spark plug
- EGR system and EGR valve leak
- Evaporative emission control system
- Compression pressure

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