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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)

"Hot" is from 50°C (122°F) to 100°C (212°F)

  1. INSPECT SPARK TEST 

    Check that the spark occurs.

    1. Remove the ignition coil (See REPLACEMENT ).
    2. Remove the spark plug.
    3. Install the spark plug to the ignition coil, and connect the ignition coil connector.
    4. Disconnect the 8 injector connectors.
    5. Ground the spark plug.
    6. See if spark occurs while engine is being cranked.
    NOTE: To prevent gasoline from being injected from injectors during this test, crank the engine for no more than 5-10 seconds at time.

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

    Fig 1: Ignition System Inspection Flow Chart
    G02951641Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. INSPECT SPARK PLUGS 
    NOTE:
    • Never use a wire brush for cleaning.
    • Never attempt to adjust the electrode gap on a used spark plug.
    • Spark plugs should be replaced every 200,000 km (120,000 miles).
    1. Remove the 8 ignition coils (See REPLACEMENT ).
    2. Inspect the electrode.
      • Using a megger (insulation resistance meter), measure the insulation resistance.

      Standard correct insulation resistance: 

      10 MΩ. or more. 

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

      Fig 2: Checking Spark Plug Insulator Resistance
      G02951642Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

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

      • Simple Method:
        • Quickly race the engine to 4,000 rpm 5 times.
        • 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

          Fig 3: Inspecting If Electrode Is Wet Or Dry
          G02951643Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        • Reinstall the spark plug (See step  c).
    3. Using a 16 mm plug wrench, remove the 8 spark plugs.
      4. Fig 4: Removing Spark Plug
      G02951644Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Visually check the spark plug for thread damage and insulator damage.

      If abnormal, replace the spark plug.

      Recommended spark plug: 

      RECOMMENDED SPARK PLUG

      DENSO made SK20R11
      NGK made IFR6A11
    5. Inspect the electrode gaps.

      Standard electrode gap: 

      1.0-1.1 mm (0.0394 - 0.043 in.) 

      Maximum electrode gap: 

      1.3 mm (0.051 in.) 

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

      Fig 5: Inspecting Electrode Gaps
      G02951645Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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.

      Air pressure: Below 588 kPa (6 kgf/cm 2  , 85 psi) 

      Duration: 20 seconds or less 

      Fig 6: Cleaning Spark Plugs
      G02951646Courtesy 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, install the 8 spark plugs.

      Torque: 17.5 N.m (180 kgf.cm, 13 ft.lbf) 

    8. Reinstall the 8 ignition coil (See REPLACEMENT ).
  3. INSPECT IGNITION COILS (WITH IGNITERS) (See step   2 ) 
  4. INSPECT CAMSHAFT POSITION SENSOR 
    1. Remove the 2 bolts, 2 cap nuts and V-bank cover.
    2. Disconnect the sensor connector.
    3. Using an ohmmeter, measure the resistance between terminals.

      Resistance: 

      CAMSHAFT POSITION SENSOR TERMINALS SPECIFICATION

      Cold 835-1,400 Ω
      Hot 1,060-1,645 Ω
      Fig 7: Measuring Resistance Between Camshaft Position Sensor Terminals
      G02951647Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the resistance is not as specified, replace the sensor (See REPLACEMENT ).

    4. Reconnect the sensor connector.
    5. Reinstall the V-bank cover with the 2 cap nuts.
  5. INSPECT CRANKSHAFT POSITION SENSOR 
    1. Remove the sensor (See REPLACEMENT ).
    2. Using an ohmmeter, measure the resistance between the terminals.

      Resistance: 

      CRANKSHAFT POSITION SENSOR TERMINALS SPECIFICATION

      Cold 1,630-2,740 Ω
      Hot 2,065-3,225 Ω
      Fig 8: Measuring Resistance Between Crankshaft Position Sensor Terminals
      G02951648Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    3. Reinstall the ssor (See REPLACEMENT ).
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