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On-Vehicle Inspection

NOTE: "Cold" and "Hot" in these sentences express the temperature of the coils themselves. "Cold" is from -10°C (14°F) to 50°C (122°F) and "Hot" is from 50°C (122°F) to 100°C (212°F).
  1. INSPECT IGNITER AND SPARK TEST 

    Check that the spark occurs.

    1. Remove the ignition coil (See REMOVAL  ).
    2. Using a 16 mm plug wrench, remove the spark plug.
    3. Install the spark plug to the ignition coil, and connect the ignition coil connector.
    4. Ground the spark plug.
    5. Check if spark occurs while engine is being cranked.
      NOTE: To prevent excess fuel being injected from the injectors during this test, do not crank the engine for more 5 - 10 seconds at a time.

      If the spark does not occur, do the test as follows:

      Fig 1: Spark Test Flow Chart
      G00892694Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Using a 16 mm plug wrench, reinstall the spark plug.
      1. Torque: 18 N.m (180 kgf.cm, 13 ft.lbf) 
    7. Reinstall the ignition coil (See INSTALLATION  ).
  2. INSPECT HIGH-TENSION CORDS 
    1. Remove the No.3 timing belt cover.
    2. Remove the throttle body gasket (See REMOVAL  ).
    3. Disconnect the high-tension cord set from the spark plugs.
      Fig 2: Identifying Correct Way Of Disconnecting High Tension Cords
      G00892695Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Disconnect the high-tension cords at the rubber boot.

      DO NOT pull on the cords.

      NOTE: Pulling on or bending the cords may damage the conductor inside.
    4. Disconnect the high-tension cord set from the ignition coils.
      1. Using a screwdriver, lift up the lock claw and disconnect the holder from the ignition coils.
      2. Disconnect the high-tension cord at the grommet.

        DO NOT pull on the cord.

      NOTE:
      • Pulling on or bending the cords may damage the conductor inside.
      • Do not wipe any of the oil from the grommet after the high-tension cord is disconnected.
      Fig 3: Disconnecting High-Tension Cord Set From Ignition Coils
      G00892696Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Using an ohmmeter, measure the resistance.
      1. Maximum resistance: 25 kΩ per cord 

      If the resistance is greater than the maximum, check the terminals. If necessary, replace the high-tension cord.

      Fig 4: Measuring Resistance Using Ohmmeter
      G00892697Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Reconnect the high-tension cord set to the ignition coils.
      1. Assemble the holder and grommet.
      2. Align the spline of the ignition coil with the spline of the holder, and push in the cord.
        Fig 5: Connecting High-Tension Cord Set To Ignition Coils
        G00892698Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        NOTE: Check that the holder is correctly installed to the grommet as shown in Fig 6 .
        Fig 6: Checking Holder Is Correctly Installed To Grommet
        G00892699Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Check that the lock claw of the holder is engaged by lightly pulling the holder.
    7. Reconnect the high-tension cord set to the spark plugs.
    8. Reinstall the throttle body gasket (See INSTALLATION  ).
    9. Reinstall the No.3 timing belt cover.
  3. INSPECT SPARK PLUGS 
    NOTE:
    • Never use a wire brush for cleaning.
    • Never attempt to adjust the electrode gap on used a spark plug.
    1. Remove the ignition coils and high-tension cord set assembly (See REMOVAL  ).
    2. Inspect the electrode.
      • Using a megger (insulation resistance meter), measure the insulation resistance.
        1. Standard correct insulation resistance: 10 MΩ or more 
        Fig 7: Measuring Insulation Resistance Using Megger
        G00892700Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        If the resistance is less than specified, proceed to step  d.

        HINT:

        If a megger is not available, the following simple method of inspection provides fairly accurate results.

      • Simple Method:
        • Quickly race the engine 5 times to 4,000 rpm.
        • Remove the spark plug (See step  c.
        • Visually check the spark plug.

          If the electrode is dry ... OK

          If the electrode is wet ... Proceed to step  d.

        • Reinstall the spark plug (See step  g.
    3. Using a 16 mm plug wrench, remove the 6 spark plugs.
    4. Visually check the spark plug for thread damage and insulator damage.
      Fig 8: Inspecting Spark Plug
      G00892701Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If abnormal, replace the spark plug.

      Recommended spark plug: 

      Fig 9: Recommended Spark Plug Chart
      G00892702Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Inspect the electrode gap.
      1. Maximum electrode gap for used spark plug: 1.2 mm (0.047 in.) 
      Fig 10: Inspecting Electrode Gap
      G00892703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

      1. Correct electrode gap for new spark plug: 1.1 mm (0.043 in.) 
      NOTE: If adjusting the gap of a new spark plug, bend only the base of the ground electrode. Do not touch the tip. Never attempt to adjust the gap on the used plug.
    6. Clean the spark plugs.

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

      1. Air pressure: Below 588 kPa (6 kgf/cm 2, 85 psi) 
      2. Duration: 20 seconds or less 
      Fig 11: Cleaning Spark Plugs
      G00892704Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      If there are traces of oil, remove it with gasoline before using the spark plug cleaner.

    7. Using a 16 mm plug wrench, reinstall the 6 spark plugs.
      1. Torque: 18 N.m (180 kgf.cm, 13 ft.lbf) 
    8. Reinstall the ignition coils and high-tension cord set assembly (See INSTALLATION  ).
  4. INSPECT IGNITION COILS 
    1. Remove the ignition coil assembly (See REMOVAL  ).
    2. Using an ohmmeter, measure the resistance between the positive (+) and negative (-) terminals.
      Fig 12: Measuring Resistance Between Terminals
      G00892705Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Primary coil resistance: 

      Fig 13: Primary Coil Resistance Chart
      G00892707Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the resistance is not as specified, replace the ignition coil.

    3. Using an ohmmeter, measure the resistance between the positive (+) and high-tension terminal.
      Fig 14: Measuring Resistance Between Positive And High-Tension Terminal
      G00892706Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Secondary coil resistance: 

      Fig 15: Secondary Coil Resistance Chart
      G00892708Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the resistance is not as specified, replace the ignition coil.

    4. Reinstall the ignition coil assembly (See INSTALLATION  ).
  5. INSPECT CAMSHAFT POSITION SENSOR 
    1. Disconnect the sensor connector.
    2. Using an ohmmeter, measure the resistance between terminals.
      Fig 16: Measuring Resistance Between Terminals
      G00892709Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Resistance: 

      Fig 17: Camshaft Position Sensor Resistance Chart
      G00892711Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the resistance is not as specified, replace the sensor.

    3. Reconnect the camshaft position sensor connector.
  6. INSPECT CRANKSHAFT POSITION SENSOR 
    1. Disconnect the sensor connector.
    2. Remove the bolt holding the connector bracket to the water pump.
    3. Using an ohmmeter, measure the resistance between terminals.
      Fig 18: Measuring Resistance Between Terminals
      G00892710Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Resistance: 

      Fig 19: Crankshaft Position Sensor Resistance Chart
      G00892712Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the resistance is not as specified, replace the sensor.

    4. Reinstall the bolt holding the connector bracket to the water pump.
    5. Reconnect the sensor connector.