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On-Vehicle Inspection

  1. PERFORM SPARK TEST 
    1. Check for DTCs.
      NOTE: If any DTC is present, perform troubleshooting procedures for that DTC.
    2. Check if sparks occur.
      1. Remove the ignition coils (see REMOVAL  ).
      2. Remove the spark plugs.
      3. Install the spark plug to the ignition coil and connect the ignition coil connector.
      4. Disconnect the 2 fuel delivery pipe connectors.
        Fig 1: Locating Fuel Delivery Pipe Connectors
        G04943787Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Disconnect the 4 connectors with wire harness locks from the 2 injector drivers.

        HINT:

        To release each connector lock, push the claw downward ("Release" in the illustration) and move the lock lever ("Move" in the illustration).

        Fig 2: Locating Wire Harness Locks And Connectors
        G04943788Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      6. Ground the spark plug.
      7. Visually check that sparks occur while the engine is being cranked.
      NOTE:
      • Be sure to ground the spark plug when checking.
      • If the ignition coil has been struck or dropped, replace it.
      • Do not crank the engine for more than 2 seconds.
    3. Perform the spark test according to the procedures below:
      Fig 3: Grounding Spark Plug
      G04943789Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Check that the wire harness side connector of the ignition coil with igniter is securely connected.

        Result 

        RESULT CHART

        Result Proceed to
        NG Connect securely
        OK Go to next step
      2. Perform a spark test on each ignition coil with igniter.
        1. If there is a cylinder where sparks do not occur, replace its ignition coil with the ignition coil of a cylinder where sparks occur normally.
        2. Crank the engine and visually check that sparks occur at the cylinder with the normally operating ignition coil.

          Result 

          RESULT CHART

          Result Proceed to
          OK Replace ignition coil with igniter
          NG Go to next step
      3. Inspect the spark plug.

        Result 

        RESULT CHART

        Result Proceed to
        NG Replace spark plug
        OK Go to next step
      4. Check the power supply to the ignition coil with igniter.
        1. Turn the engine switch on (IG).
        2. Check that there is battery voltage at the ignition coil positive (+) terminal.

          Result 

          RESULT CHART

          Result Proceed to
          NG Check wiring between engine switch and ignition coil with igniter
          OK Go to next step
      5. Check the VVT sensor (see ON-VEHICLE INSPECTION ).
      6. Check the camshaft position sensor (see ON-VEHICLE INSPECTION ).
      7. Check the crankshaft position sensor (see ON-VEHICLE INSPECTION ).
      8. Check the IGT signal circuit (see DESCRIPTION ).
    4. Using a 16 mm plug wrench, install the spark plug.

      Torque: 18 N*m (184 kgf*cm, 13 ft.*lbf) 

    5. Connect the 4 connectors with wire harness locks to the 2 injector drivers.
      NOTE: Connect the connector securely.

      HINT:

      Move the lock lever in the direction indicated by the arrow to lock the connector.

      Fig 4: Locating Wire Harness Locks And Connectors
      G04943790Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Connect the 2 fuel delivery pipe connectors.
    7. Install the ignition coils (see INSTALLATION  ).
  2. INSPECT SPARK PLUG 
    NOTE:
    • Do not use a wire brush for cleaning.
    • Do not attempt to adjust the electrode gap of a used spark plug.
      Fig 5: Locating Fuel Delivery Pipe Connectors
      G04943787Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the electrode.
      1. Using a megohmmeter, measure the insulation resistance.

        Standard insulation resistance: 10 MΩ or more 

        HINT:

        If a megohmmeter is not available, perform the following simple inspection instead.

        Fig 6: Measuring Insulation Resistance
        G04943792Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Alternative inspection method:
      1. Quickly accelerate the engine to 4,000 rpm 5 times.
      2. Remove the spark plug.
      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.

        Fig 7: Checking Spark Plug
        G04943793Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Check the spark plug for any damage to its threads and insulator.

      If there is any damage, replace the spark plug. If not, reinstall the spark plug.

      Recommended spark plug 

      SPARK PLUG SPECIFICATION

      Manufacturer Product
      DENSO made FK20HBR11
      Fig 8: Checking Spark Plug
      G04943794Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      Maximum electrode gap for a used spark plug: 1.3 mm (0.051 in.)

      If the gap is greater than the maximum, replace the spark plug.

      Electrode gap for a new spark plug: 1.0 to 1.1 mm (0.039 to 0.043 in.)

      Fig 9: Identifying Electrode Gap
      G04943795Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE: Never attempt to adjust the gap of a used plug.

      If the electrode has traces of wet carbon, allow it to dry and then clean it with a spark plug cleaner.

      Standard air pressure: 

      588 kPa (6 kgf/cm 2  , 85 psi) 

      Standard duration: 20 seconds or less 

      Fig 10: Cleaning Electrode With Spark Plug Cleaner
      G04943796Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      Only use the spark plug cleaner when the electrode is free of oil. If the electrode has traces of oil, use gasoline to clean off the oil before using the spark plug cleaner.

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