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Engine Mechanical: Co/HC: Inspection

HINT:

This check is used only to determine whether or not the idle CO/HC complies with regulations.

  1. INITIAL CONDITIONS 
    1. The engine is at normal operating temperature.
    2. Air cleaner is installed.
    3. All pipes and hoses of the air induction system are connected.
    4. All accessories are switched OFF.
    5. All vacuum lines are properly connected.

      HINT:

      All vacuum hoses should be properly connected.

    6. SFI system wiring connectors are fully plugged.
    7. Ignition timing is set correctly.
    8. Transmission is in neutral range.
    9. Tachometer and CO/HC meter are calibrated by hand.
  2. START ENGINE 
  3. RACE ENGINE AT 2,500 RPM FOR APPROX. 180 SECONDS 
  4. INSERT CO/HC METER TESTING PROBE AT LEAST 40 cm (1.3 ft) INTO TAILPIPE DURING IDLING 
    Fig 1: Inserting CO/HC Meter Testing Probe
    G00913834Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. IMMEDIATELY CHECK CO/HC CONCENTRATION AT IDLE AND/OR 2,500 RPM 

    HINT:

    When performing the 2 mode (2,500 RPM and idle) test, follow the measurement order prescribed by the applicable local regulations.

  6. TROUBLESHOOTING 

    If the CO/HC concentration does not comply with the regulations, perform troubleshooting in the order in Fig 2 .

    Fig 2: Troubleshooting Table
    G00913835Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002