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On-Vehicle Inspection

  1. PERFORM SPARK TEST 
    1. Check for DTCs. Refer to DTC CHECK / CLEAR .
      NOTE:

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

    2. Check if sparks occur.
      1. Remove the ignition coils and spark plugs. Refer to REMOVAL .
      2. Install the spark plug to the ignition coil and connect the ignition coil connector.
      3. Disconnect the 8 injector connectors.
      4. Ground the spark plug.
      5. 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. Check that the wire harness side connector of the ignition coil is securely connected.
      RESULT

      Result Proceed to
      NG Connect securely
      OK Go to next step
    4. Perform a spark test on each ignition coil.
      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 Proceed to
        OK Replace ignition coil
        NG Go to next step
    5. Inspect the spark plug.
      1. Replace the spark plug with a normal one.
      2. Perform a spark test.
        RESULT

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

        Result Proceed to
        NG Check wiring between battery and ignition coil
        OK Go to next step
    7. Check the VVT sensor for the intake camshaft. Refer to DTC P0340: Camshaft Position Sensor Circuit Malfunction; DTC P0342: Camshaft Position Sensor "A" Circuit Low Input (Bank 1 or Single Sensor); DTC P0343: Camshaft Position Sensor "A" Circuit High Input (Bank 1 or Single Sensor); DTC P0345: Camshaft Position Sensor "A" Circuit (Bank 2); DTC P0347: Camshaft Position Sensor "A" Circuit Low Input (Bank 2); DTC P0348: Camshaft Position Sensor "A" Circuit High Input (Bank 2) .
    8. Check the VVT sensor for the exhaust camshaft. Refer to DTC P0365: Camshaft Position Sensor "B" Circuit (Bank 1); DTC P0367: Camshaft Position Sensor "B" Circuit Low Input (Bank 1); DTC P0368: Camshaft Position Sensor "B" Circuit High Input (Bank 1); DTC P0390: Camshaft Position Sensor "B" Circuit (Bank 2); DTC P0392: Camshaft Position Sensor "B" Circuit Low Input (Bank 2); DTC P0393: Camshaft Position Sensor "B" Circuit High Input (Bank 2) .
    9. Check the camshaft position sensor. Refer to DTC P1340: Camshaft Position Sensor "A" (Bank 1 Sensor 2); DTC P1342: Camshaft Position Sensor "A" Low Input (MRE); DTC P1343: Camshaft Position Sensor "A" High Input (MRE) .
    10. Check the crankshaft position sensor. Refer to DTC P0335: Crankshaft Position Sensor "A" Circuit; DTC P0337: Crankshaft Position Sensor "A" Circuit Low Input; DTC P0338: Crankshaft Position Sensor "A" Circuit High Input; DTC P0339: Crankshaft Position Sensor "A" Circuit Intermittent .
    11. Check the IGT signal circuit. Refer to DTC P0351: Ignition Coil "A" Primary / Secondary Circuit; DTC P0352: Ignition Coil "B" Primary / Secondary Circuit; DTC P0353: Ignition Coil "C" Primary / Secondary Circuit; DTC P0354: Ignition Coil "D" Primary / Secondary Circuit; DTC P0355: Ignition Coil "E" Primary / Secondary Circuit; DTC P0356: Ignition Coil "F" Primary / Secondary Circuit; DTC P0357: Ignition Coil "G" Primary / Secondary Circuit; DTC P0358: Ignition Coil "H" Primary / Secondary Circuit .
    12. Connect the 8 injector connectors.
    13. Install the ignition coils and spark plugs. Refer to 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.
    1. Check the electrode.
      1. Using a megohmmeter, measure the insulation resistance.
        Fig 1: Identifying Megohmmeter For Insulation Resistance
        GTY258353Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Insulation Resistance

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

        *1 Ground

        If the result is not as specified, replace the spark plug.

        HINT: 

        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.
      3. Visually check the spark plug.
        Fig 2: Identifying Spark Plug Condition
        GTY146371Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        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 Type
      DENSO SK20HR11
    4. Check the spark plug electrode gap.

      Maximum electrode gap for a used spark plug

      1.3 mm (0.0512 in.)

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

      Electrode gap for a new spark plug

      1.0 to 1.1 mm (0.0394 to 0.0433 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 of a used plug.

      Fig 3: Cleaning Electrode With Spark Plug Cleaner
      GTY122118Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      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 (6.0 kgf/cm2 , 85 psi)

      Standard duration

      20 seconds or less

      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.