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On-Vehicle Inspection

  1. PERFORM SPARK TEST 
    1. Check for DTCs (See 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 (See 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.
      Fig 1: Attaching Spark Plug Assembly To Cylinder Head
      G05149766Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Check that the wire harness side connector of the ignition coil with igniter is securely connected.

      Result 

      RESULT REFERENCE

      Result Proceed to
      NG Connect securely
      OK Go to next step
    4. 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 REFERENCE

      Result Proceed to
      OK Replace ignition coil with igniter
      NG Go to next step
    5. Check spark plug.

      Result 

      RESULT REFERENCE

      Result Proceed to
      NG Replace spark plug
      OK Go to next step
    6. 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 REFERENCE

      Result Proceed to
      NG Check wiring between engine switch and ignition coil with igniter
      OK Go to next step
    7. Check the VVT sensor for intake side (See 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 exhaust side (See 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 (See 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 (See 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 (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; 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 (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.
    1. Check the electrode.
      1. Using a megohmmeter, measure the insulation resistance.

        Standard Insulation Resistance 

        TESTER CONNECTION SPECIFIED CONDITION CHART

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

        If the insulation resistance is below the specified range, 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.
        Fig 2: Measuring Insulation Resistance
        G05157894Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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.

    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 

      SPARK PLUG SPECIFICATION

      Manufacturer Type
      DENSO made SK20HR11
      Fig 3: Checking Spark Plug
      G04975478Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    HINT:

    Maximum electrode gap for a used spark plug: 1.3 mm (0.051 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 (0.039 to 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 of a used plug.
    Fig 4: Identifying Spark Plug Electrode Gap
    G05157896Courtesy 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/cm 2  , 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.

    Fig 5: Cleaning Spark Plug
    G04943796Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002