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Ignition System: Inspection

NOTE: In this article, 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 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 an megaohmmeter, measure the insulation resistance.

        Correct insulation resistance: 10 MΩ or higher 

        Fig 1: Checking Electrode
        G02999161Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

      HINT:

      If the megaohmmeter is not available, perform the following simple inspection instead.

    2. Alternative inspection method:
      1. Quickly accelerate the engine to 4,000 rpm 5 times.
      2. Remove the spark plug.
      3. Visually check the spark plug.
      • If the electrode is dry, the spark plug is functioning. Reinstall the spark plug. Proceed to step  3.
      • If the electrode is damp, proceed to steps (c), ( d) and ( e).
      Fig 2: Alternative Inspection Method
      G02999162Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Check the spark plug for any damage on its thread and insulator.

      If there is any damage, replace the spark plug. If not, reinstall the spark plug.

      RECOMMENDED SPARK PLUG TABLE

      DENSO made SK20R11
      NGK made IFR6A11
    4. Check the spark plug electrode gap.
      1. Maximum electrode gap for used spark plug: 1.3 mm (0.051 in.) 

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

      1. Correct electrode gap for new spark plug: 1.0 to 1.1 mm (0.039 to 0.043 in.) 
      2. Fig 3: Checking Spark Plug Electrode Gap
        G02999163Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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 a used plug.
    5. Clean the spark plugs.

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

      Fig 4: Cleaning Spark Plugs
      G02999164Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Air pressure: 588 kPa (6 kgf/cm 2  , 85 psi) 
      2. 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.

  2. INSPECT CAMSHAFT POSITION SENSOR 
    1. Using an ohmmeter, measure the resistance between the terminals.
    CAMSHAFT POSITION SENSOR - REFERENCE TABLE

    Condition Specified Condition
    Cold 835 to 1,400 Ω
    Hot 1,060 to 1,645 Ω
    Fig 5: Inspecting Camshaft Position Sensor
    G02999165Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  3. INSPECT CRANKSHAFT POSITION SENSOR 
    1. Using an ohmmeter, measure the resistance between the terminals.
    CRANKSHAFT POSITION SENSOR - REFERENCE TABLE

    Condition Specified Condition
    Cold 1,630 to 2,740 Ω
    Hot 2,065 to 3,225 Ω
    Fig 6: Inspecting Crankshaft Position Sensor
    G02999166Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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