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On-Vehicle Inspection

  1. INSPECT MASS AIR FLOW METER 
    NOTE:
    • Perform the MAF meter inspection by following the procedures below.
    • Only replace the MAF meter when both the LONG FT#1 value and MAF value in the DATA LIST (with the engine stopped) are not within the normal operating range.
    1. Perform confirmation driving pattern.
      1. Connect the intelligent tester to the DLC3.
      2. Turn the ignition switch to the ON position.
      3. Turn the tester on.
      4. Clear the DTCs (See DTC CHECK/CLEAR  ).
      5. Start the engine and warm it up with all accessory switches off (until the engine coolant temperature is 75°C (167°F) or more).
      6. Drive the vehicle at 31 mph (50 km/h) or more for 3 minutes or more (*1).
      7. Let the engine idle (accelerator pedal fulley released) for 2 minutes or more (*2).
      8. Perform steps (*1) and (*2) at least 3 times or more.
        Fig 1: Connecting Intelligent Tester To DLC3
        G05202415Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Fig 2: Vehicle Speed Graph
        G04973340Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Read value using the intelligent tester (LONG FT#1).
      1. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / LONG FT#1.
      2. Read the values displayed on the tester.

        Standard value: 

        Within -15 to +15% 

        If the result is not within the specified range, perform the inspection below.

    3. Read the values using the intelligent tester (MAF).
      NOTE:
      • Turn off the engine.
      • Perform the inspection with the vehicle indoors and on a level surface.
      • Perform the inspection of the MAF meter while it is installed to the air cleaner case (installed to the vehicle).
      • During the test, do not use the exhaust air duct to perform suction on the exhaust pipe.
      1. Turn off the engine (do not run the engine).
      2. Turn the ignition switch to the ON position.
      3. Turn the tester on.
      4. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / PRIMARY / MAF.
      5. Wait 30 seconds, and read the values on the intelligent tester.

        Standard condition: 

        Less than 0.50 g/s 

        • If the result is not as specified, replace the MAF meter.
        • If the result is within the specified range, inspect the cause of the extremely rich or lean air fuel ratio.
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