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On-Vehicle Inspection

NOTE: In this section, the terms "cold" and "hot" refer to the temperature of the coils. "Cold" means approximately -10°C (14°F) to 50°C (122°F). "Hot" means approximately 50°C (122°F) to 100°C (212°F).
  1. INSPECT IGNITION COIL ASSEMBLY 
    1. Check for DTCs.
      NOTE: If any DTC is present, perform troubleshooting in accordance with the procedures for that DTC.
    2. Check that sparks occur.
      1. Remove the intake air surge tank (See REMOVAL ).
      2. Remove the No. 1 surge tank stay (see REMOVAL  ).
      3. Disconnect the 6 ignition coil connectors and remove the 6 bolts and 6 ignition coils.
        Fig 1: Locating Ignition Coil Connectors
        G05248778Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Using a 16 mm (0.63 in.) plug wrench, remove the 6 spark plugs.
        Fig 2: Identifying Spark Plugs
        G05248779Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Disconnect the 6 fuel injector connectors.
      6. Install the spark plugs to each ignition coil, and connect the ignition coil connectors.
        Fig 3: Locating Fuel Injector Connectors
        G04975488Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      7. Ground the spark plugs.
      8. Check if a spark occurs at each spark plug while the engine is being cranked.
        NOTE:
        • Be sure to ground the spark plugs when checking.
        • Replace the ignition coil if it receives an impact.
        • Do not crank the engine for more than 2 seconds.
          Fig 4: Checking Ground Spark Plugs
          G04975489Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Perform the spark test according to the flowchart below.
      1. Check that the ignition coil connector is securely connected.

        Result 

        RESULT REFERENCE

        Result Proceed to
        NG Connect securely
        OK Go to Next Step
      2. Perform a speak test on each ignition coil.
        1. Replace the ignition coil with a normal one.
        2. Perform the spark test again.

          Result 

          RESULT REFERENCE

          Result Proceed to
          OK Replace Ignition coil
          NG Go to Next Step
      3. Check the power supply to the ignition coil.
        1. Turn the engine switch on (IG).
        2. Measure the voltage between the terminals of the wire harness side connector.

          Standard voltage 

          STANDARD VOLTAGE SPECIFICATION

          Tester Connection Specified Condition
          1 (+B) - 4 (GND) 9 to 14 V

          Result 

          RESULT REFERENCE

          Result Proceed to
          NG Check wiring between engine switch and ignition coil
          OK Go to Next Step
      4. Measure the resistance of the crankshaft position sensor.
        Fig 5: Measuring Voltage Between Terminals Of Wire Harness Side Connector
        G04975490Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard resistance 

        STANDARD RESISTANCE SPECIFICATION

        Temperature Specified Condition
        Cold 1,630 to 2,740 Ω
        Hot 2,065 to 3,225 Ω

        Result 

        RESULT REFERENCE

        Result Proceed to
        NG Replace crankshaft position sensor
        OK Go to Next Step
      5. Check the IGT signal from the ECM.

        Result 

        RESULT REFERENCE

        Result Proceed to
        NG Check ECM (See 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 )
        OK Repair wiring between ignition coil and ECM
    4. Using a 16 mm (0.63 in.) plug wrench, install the spark plugs.

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

      Fig 6: Identifying Spark Plugs
      G05248779Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Install the 6 ignition coils with the 6 bolts and connect the 6 ignition coil connectors.

      Torque: 10 N*m (102 kgf*cm, 7 ft.*lbf) 

      Fig 7: Locating Ignition Coil Connectors
      G05248778Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Connect the 6 fuel injector connectors.
    7. Install the No. 1 surge tank stay (See INSTALLATION  ).
    8. Install the intake air surge tank (See INSTALLATION ).
  2. INSPECT SPARK PLUG 
    NOTE:
    • Never use a wire brush for cleaning.
    • Never attempt to adjust the electrode gap on a used spark plug.
      Fig 8: Locating Fuel Injector Connectors
      G04975488Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the electrode.
      1. Using a megohmmeter, measure the insulation resistance.

        Standard insulation resistance: 10 MΩ or higher 

        HINT:

        • If the result is 10 MD or less, clean the plug and measure the resistance again.
        • If a megohmmeter is not available, perform the following simple inspection instead.
          Fig 9: Measuring Insulation Resistance
          G04975477Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Alternative inspection method:
      1. Quickly accelerate the engine to 4,000 rpm 5 times.
      2. Remove the spark plugs.
      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 damage, replace the spark plug.

      Require spark plug 

      REQUIRE SPARK PLUG

      Manufacturer Spark plug type
      DENSO made FK20HR11
      NOTE: Use only the listed spark plug or equivalent to ensure engine performance and smooth driveability.
    4. Check the spark plug electrode gap.

      Maximum electrode gap for a used spark plug: 1.4 mm (0.055 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 10: Identifying Spark Plug Electrode Gap
      G04975479Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Clean the spark plugs.

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

      Standard air pressure: 588 kPa (6 kgf*cm 2  , 85 psi) 

      Standard duration: 20 seconds or less 

      Fig 11: Cleaning Spark Plugs
      G04962921Courtesy 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.