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On-Vehicle Inspection [12/2021 - ]: Procedure

  1. PERFORM SPARK TEST 
    WARNING:

    To prevent injury due to contact with an operating cooling fan, keep your hands and clothing away from the cooling fans when working in the engine compartment with the engine running or the ignition switch on (IG).

    GTY579837Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    HINT: 

    Perform "Inspection After Repair" after replacing an ignition coil assembly or spark plug.

    1. Check for DTCs.
      NOTE:

      If any DTC is output, perform the troubleshooting procedures for that DTC.

    2. Remove the 6 ignition coil assemblies and 6 spark plugs.

      Refer to REMOVAL [12/2021 - ]

      NOTE:

      If an ignition coil assembly or spark plug has been struck or dropped, replace it.

    3. Disconnect the 4 connectors.
      GTY1074658Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Install the spark plug to the ignition coil assembly and connect the ignition coil assembly connector.
    5. Ground the spark plug.
    6. Check that spark occurs at each spark plug while the engine is being cranked.
      NOTE:
      • When performing the inspection, be sure to ground the hexagonal portion or the threaded portion of the spark plug.
      • Do not crank the engine for more than 2 seconds.

        For vehicles with a cranking hold function, turn the ignition switch off during cranking to stop cranking.

      • If an ignition coil assembly or spark plug has been struck or dropped, replace it.

      HINT: 

      If spark does not occur, perform the following procedure.

  2. INSPECT IGNITION COIL ASSEMBLY AND SPARK TEST 

    HINT: 

    Perform "Inspection After Repair" after replacing a ignition coil assembly or spark plug.

    1. Check that the ignition coil assembly connector is securely connected.

      Result

      Result Action
      NG Connect securely
      OK Go to next step
    2. Perform a spark test on each ignition coil assembly.
      1. Replace the ignition coil assembly with a known good one.
      2. Perform the spark test again.

        Result

        Result Action
        NG Go to next step
        OK Replace ignition coil assembly
        NOTE:

        If a ignition coil assembly or spark plug has been struck or dropped, replace it.

    3. Perform a spark test on each spark plug.
      1. Replace the spark plug with a known good one.
      2. Perform the spark test again.

        Result

        Result Action
        NG Inspect the ignition system
        OK Replace spark plug
        NOTE:

        If a ignition coil assembly or spark plug has been struck or dropped, replace it.

    4. Connect the 4 connectors.
    5. Install the 6 ignition coil assemblies and 6 spark plugs.

      Refer to INSTALLATION [12/2021 - ]

    6. Check for DTCs.
    7. Clear the DTCs.
  3. CHECK SPARK PLUG 
    NOTE:
    • Do not damage the iridium tip and platinum tip.
    • Check the iridium tip visually since the iridium tip may be damaged.
    • Never attempt to adjust the electrode gap of a used spark plug.
    • Replace with new spark plugs if extremely dirty due to sludge, etc.
    • Replace with new spark plugs if damaged at all.
    • Replace with a new spark plug if it has been struck or dropped.
    • When replacing with a new spark plug, do not remove the cap for protecting the spark plug tip until it is installed to the engine.

    HINT: 

    Perform "Inspection After Repair" after replacing a spark plug.

    1. Check the electrode.
      GTY425641Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Body Ground
      1. Using a megohmmeter, measure the insulation resistance.

        Standard Insulation Resistance

        Tester Connection Condition Specified Condition
        Spark plug (terminal part) - Body ground Always 10 MΩ or higher

        HINT: 

        • If the result is not as specified, clean the spark plug with a spark plug cleaner and measure the resistance again.
        • If a megohmmeter is not available, perform the following simple inspection instead.
    2. Alternative inspection method.
      1. Quickly accelerate the engine to 4000 rpm 5 times.
      2. Remove the spark plug.

        Refer to REMOVAL [12/2021 - ]

      3. Visually check the spark plug.

        If the electrode is dry, the spark plug is functioning properly. If the electrode is damp, proceed to the next step.

    3. Check the spark plug for any damage to its threads and insulator.

      If there is any damage, replace the spark plug.

      Recommended Spark Plug

      Manufacturer Spark Plug Type
      DENSO EC22HPR-D7
    4. Check the spark plug electrode gap.

      Maximum Electrode Gap for Used Spark Plug

      0.9 mm (0.0354 in.)

      NOTE:

      Never attempt to adjust the electrode gap of a used spark plug.

      If the spark plug electrode gap is more than the maximum, replace the spark plug.

      Standard Electrode Gap for New Spark Plug

      0.6 to 0.7 mm (0.0237 to 0.0275 in.)

    5. Install the spark plug.

      Refer to INSTALLATION [12/2021 - ]

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