2004 Lexus LX 470FACTORY OEM SERVICE PROCEDURE

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) and "Hot" is from 50°C (122°F) to 100°C (212°F). 
  1. INSPECT IGNITION COIL (WITH IGNITER) AND SPARK TEST 

    Check that the spark occurs.

    1. Remove the ignition coils (with igniter) (See REMOVAL ).
    2. Remove the spark plugs.
    3. Install the spark plugs to each ignition coil (with igniter), and connect the ignition coil (with igniter) connector.
    4. Disconnect the 8 injector connectors.
    5. Ground the spark plug.
    6. Check 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: Spark Test
      G00920811Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. Using a 16 mm plug wrench, install the spark plugs.
      1. Torque: 17.5 N.m (180 kgf.cm, 13 ft.lbf) 
    8. Reinstall the ignition coils (with igniter) (See REMOVAL ).
  2. INSPECT SPARK PLUGS 
    NOTE:
    • Never use a wire brush for cleaning. 
    • Never attempt to adjust the electrode gap on used spark plug. 
    • Spark plug should be replaced every 100,000 km (60,000 miles). 
    1. Remove the ignition coils (with igniter) (See REMOVAL ).
    2. Check the electrode.
      • Using a merger (insulation resistance meter), measure the insulation resistance.
        1. Correct insulation resistance: 10 MΩ or more 

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

        HINT:

        If a merger is not available, the following simple method of inspection provides fairly accurate results.

        Fig 2: Checking Electrodes
        G00920812Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • 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).

        • Reinstall the spark plug. (See step  g)
        Fig 3: Checking Spark Plug
        G00920813Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Using a 16 mm plug wrench, remove the spark plugs.
      Fig 4: Removing Spark Plugs
      G00920814Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Check the spark plug for thread damage and insulator damage.

      If abnormal, replace the spark plug.

      Recommended spark plug: 

      RECOMMENDED SPARK PLUG TABLE

      DENSO made SK20R11
      NGK made IFR6A11
      Fig 5: View Of Spark Plug
      G00920815Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Check the spark plug electrode gap.
      1. Maximum electrode gap for used spark plug: 1.2 mm (0.047 in.) 

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

      1. Correct electrode gap for new spark plug: 1.1 mm (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 on a used plug. 
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.