Ignition System On-Vehicle Inspection

Engine. Lexus Gs430, Gs300. Uzs190 Grs190
3Uz-Fe Ignition. Lexus Gs430, Gs300. Uzs190 Grs190

  1. PERFORM SPARK TEST

  2. CHECK SPARK PLUG

Ignition System -- On-Vehicle Inspection


NOTICE:
In this section, the terms "cold" and "hot" refer to the temperature of the coils. "Cold" means approximately -10 to 50°C (14 to 122°F). "Hot" means approximately 50 to 100°C (122 to 212°F).


1. PERFORM SPARK TEST
  1. Check for DTCs.

    NOTICE:
    If a DTC is present, perform troubleshooting procedures for that DTC.
  1. Check if sparks occur.

    1. Remove the ignition coil.

    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. Visually check that sparks occur while the engine is being cranked.

      NOTICE:
      1. Be sure to ground the spark plugs when checking them.
      2. If the ignition coil has been struck or dropped, replace it.
      3. Do not crank the engine for more than 2 seconds.
  1. Perform the Spark test according to the flowchart below.

    1. Check that the wire harness side connector of the ignition coil with igniter is securely connected.

      Result:
      Result
      Proceed to
      NG
      Connect securely
      OK
      Go to next step
    2. Perform a spark test on each ignition coil with igniter.

      1. 1. Replace the ignition coil with igniter with a normal one.
      2. 2. Perform the spark test again.
        Result:
        Result
        Proceed to
        OK
        Replace ignition coil with igniter
        NG
        Go to next step
    3. Check the power supply to the ignition coil with igniter.

      1. 1. Turn the ignition switch on (IG).
      2. 2. Check that there is battery voltage at the ignition coil positive (+) terminal.
        Result:
        Result
        Proceed to
        NG
        Check wiring between engine switch and ignition coil with igniter
        OK
        Go to next step
    4. Check resistance of camshaft position sensor.

      Standard resistance:
      Temperature
      Specified Condition
      Cold
      835 to 1,400 Ω
      Hot
      1,060 to 1,645 Ω
      Result:
      Result
      Proceed to
      NG
      Replace camshaft position sensor
      OK
      Go to next step
    5. Check resistance of crankshaft position sensor.

      Standard resistance:
      Temperature
      Specified Condition
      Cold
      835 to 1,400Ω
      Hot
      1,060 to 1,645Ω
      Result:
      Result
      Proceed to
      NG
      Replace crankshaft position sensor.
      OK
      Go to next step
    6. Check IGT signal from ECM.

      Result:
      Result
      Proceed to
      NG
      Check ECM
      OK
      Repair wiring between ignition coil and ECM
  1. Using a 16 mm plug wrench, install the spark plug.

    Torque:
    18 N*m{183 kgf*cm, 13 ft.*lbf}
  1. Install the ignition coil.



2. CHECK SPARK PLUG
NOTICE:
  1. Do not use a wire brush for cleaning.
  2. Do not attempt to adjust the electrode gap of a used spark plug.


    Lexus Gs430, Gs300. Uzs190 Grs190.3Uz-Fe Ignition.Ignition System.Ignition System  On-Vehicle Inspection
  1. Check the electrode.

    1. Using a megohmmeter, measure the insulation resistance.

      Insulation resistance:
      10 MΩ or more
      HINT:
      If a megohmmeter is not available, perform the following simple inspection instead.


    Lexus Gs430, Gs300. Uzs190 Grs190
  1. 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 properly. If the electrode is damp, proceed to the next step.

  1. Check the spark plug for any damage on its thread and insulator.
    If there is damage, replace the spark plug. If not, reinstall the spark plug.

    Recommended spark plug:
    DENSO made
    SK20R11
    NGK made
    IFR6A11


    Lexus Gs430, Gs300. Uzs190 Grs190.3Uz-Fe Ignition.Ignition System.Ignition System  On-Vehicle Inspection
  1. Check the spark plug electrode gap.

    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.
    Electrode gap for new spark plug:
    1.0 to 1.1 mm (0.039 to 0.043 in.)
    NOTICE:
    When 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.