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On-Vehicle Inspection

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT ENGINE COOLANT 

    See COOLING SYSTEM

  2. INSPECT ENGINE OIL 

    See LUBRICATION SYSTEM

  3. INSPECT BATTERY 

    See ON-VEHICLE INSPECTION

  4. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 
    1. Remove the air cleaner cap sub-assembly (See REMOVAL ).
    2. Remove the air filter element sub-assembly
    3. Visually check that the air filter is not excessively damaged or oily If necessary, replace the air filter.
    4. Install the air filter element sub-assembly
    5. Install the air cleaner cap sub-assembly (See INSTALLATION ).
  5. CHECK V-RIBBED BELT  (See ON-VEHICLE INSPECTION )
  6. INSPECT V-RIBBED BELT TENSIONER ASSEMBLY 
    1. Remove the V-ribbed belt (See REMOVAL )
    2. Check that nothing is caught in the tensioner by turning it clockwise and counterclockwise.

      If a malfunction exists, replace the tensioner

    3. Install the V-ribbed belt (See INSTALLATION )
  7. INSPECT IGNITION TIMING 
    1. Warm up and stop the engine.

      HINT

      A warmed up engine should have an engine coolant temperature of over 80°C (176°F), an engine oil temperature of 60°C (140°F), and the engine speed should be stabilized

      Fig 1: Inspecting V-Ribbed Belt Tensioner Assembly
      G04943148Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. When using the Techstream
      1. Connect the Techstream to the DLC3.
      2. Start the engine and run it at idle.
      3. Turn the Techstream main switch on
      4. Enter the following menus Powertrain / Engine / Data List / IGN Advance

        Standard ignition timing: 

        8 to 18° BTDC at idle 

        NOTE:
        • Check the ignition timing with the cooling fans off.
        • Turn off all electrical systems and the A/C.
        • When checking the ignition timing, the transmission should be in neutral or park.

        HINT:

        Refer to the Techstream operator's manual for further details

      5. Check that the ignition timing advances immediately when the engine speed is increased.
      6. Enter the following menus Powertrain / Engine / Active Test / Connect the TC and TE1
      7. Monitor IGN Advance
      8. Perform the Active test.

        Standard ignition timing: 

        8 to 12° BTDC at idle 

        NOTE: When checking the ignition timing, the transmission should be in neutral or park.

        HINT

        Refer to the Techstream operator's manual for further details.

    3. When not using the Techstream.
      1. Remove the V-bank cover sub-assembly (See REMOVAL )
      2. Remove the cool air intake duct seal (See REMOVAL )
      3. Remove the engine room side cover LH (See REMOVAL ).
      4. Connect the timing light tester probe to the ignition coil wire for No. 1 cylinder.
        NOTE: Use a timing light that detects primary signals.
        Fig 2: Identifying Ignition Coil Wire
        G04943149Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Using SST, connect terminals 13 (TC) and 4 (CG) of the DLC3

        SST 09843-18040 

        Fig 3: Identifying DLC3 Terminals
        G04943150Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        NOTE:
        • Confirm the terminal numbers before connecting them. Connecting the wrong terminals can damage the engine.
        • Check the ignition timing with the cooling fans off.
        • Turn off all the electrical systems and the A/C.
        • When checking the ignition timing, the transmission should be in neutral or park.
      6. Using a timing light, check the ignition timing

        Standard ignition timing: 

        8 to 12° BTDC at idle 

      7. Remove SST from the DLC3
      8. Check the ignition timing

        Standard ignition timing: 

        8 to 18° BTDC at idle 

        Fig 4: Checking Ignition Timing
        G05749373Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      9. Check that the ignition timing advances immediately when the engine speed is increased.
      10. Disconnect the timing light from the engine
      11. Install the engine room side cover LH (See INSTALLATION ).
      12. Install the cool air intake duct seal (See INSTALLATION ).
      13. Install the V-bank cover sub-assembly (See INSTALLATION )
  8. INSPECT ENGINE IDLE SPEED 
    1. Warm up and stop the engine

      HINT.

      A warmed up engine should have an engine coolant temperature of over 80°C (176°F), an engine oil temperature of 60°C (140°F), and the engine speed should be stabilized

    2. When using the Techstream
      1. Connect the Techstream to the DLC3
      2. Start the engine and run it at idle.
      3. Turn the Techstream main switch on.
      4. Enter the following menus. Powertrain / Engine / Data List / Engine Speed.

        Standard idle speed: 

        700 to 800 rpm 

        NOTE:
        • Check the idle speed with the cooling fans off.
        • Turn off all the electrical systems and the A/C.
        • When checking the idle speed, the transmission should be in neutral or park.

        HINT

        Refer to the Techstream operator's manual for further details.

        If the idle speed is not as specified, check the air intake system (See ON-VEHICLE INSPECTION )

    3. When not using the Techstream.
      1. Using SST, connect a tachometer probe to terminal 9 (TAC) of the DLC3

        SST 09843-18040 

        NOTE: Confirm the terminal numbers before connecting them. Connecting the wrong terminals can damage the engine.
        Fig 5: Identifying DLC3 Terminals
        G04943152Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Check the idle speed

        Standard idle speed: 

        700 to 800 rpm 

        NOTE:
        • Check the idle speed with the cooling fans off.
        • Turn off all the electrical systems and the A/C.
        • When checking the idle speed, the transmission should be in neutral or park.

        HINT

        If the speed is not as specified, check the air intake system (See ON-VEHICLE INSPECTION ).

  9. INSPECT COMPRESSION 
    1. Warm up and stop the engine

      HINT

      A warmed up engine should have an engine coolant temperature of over 80°C (176°F), an engine oil temperature of 60°C (140°F), and the engine speed should be stabilized.

    2. Disconnect the cable from the negative (-) battery terminal
      NOTE: When disconnecting the cable, some systems need to be initialized after the cable is reconnected (See INITIALIZATION ).
    3. Remove the air cleaner cap sub-assembly (See REMOVAL )
    4. Remove the battery.
    5. Remove the 8 spark plugs (See REMOVAL )
    6. Disconnect the throttle body connector
    7. Disconnect the 2 injector connectors as shown in the illustration.
      Fig 6: Locating Injector Connectors
      G05749375Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    8. Disconnect the 4 injector connectors as shown in the illustration.
      Fig 7: Disconnecting Injector Connectors
      G05749376Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    9. Insert a compression gauge into the spark plug hole.
    10. Install the battery
    11. Connect the cable to the negative (-) battery terminal.
      Fig 8: Checking Compression Pressure
      G04943157Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    12. Fully open the throttle valve.
    13. Depress and hold the brake pedal, and turn the engine switch on (IG). Then check the compression pressure.

      Standard compression pressure: 

      1400 kPa (14.0 kgf/cm 2  , 203 psi) or more 

      Minimum pressure: 

      980 kPa (10.0 kgf/cm 2  , 142 psi) 

      Pressure difference: 

      100 kPa (1.0 kgf/cm 2  , 14.5 psi) or less 

      NOTE: The measurement must be done as quickly as possible.

      HINT

      Always use a fully charged battery to obtain engine speed of 250 rpm or more.

    14. If the cylinder compression is low in one or more cylinders, pour a small amount of engine oil into the cylinder with low compression through its spark plug hole. Then inspect the cylinder compression pressure again

      HINT.

      • If adding oil helps boost the compression, it is likely that the piston rings and/or cylinder bore are worn or damaged.
      • If pressure stays low, a valve may be stuck or seated improperly, or there may be leakage in the gasket
    15. Disconnect the cable from the negative (-) battery terminal
    16. Remove the battery.
    17. Connect the 4 injector connectors as shown in the illustration
      Fig 9: Connecting Injector Connectors
      G05749378Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    18. Connect the 2 injector connectors as shown in the illustration.
    19. Connect the throttle body connector
    20. Install the 8 spark plugs (See INSTALLATION ).
    21. Install the battery.
    22. Install the air cleaner cap sub-assembly (See INSTALLATION ).
    23. Connect the cable to the negative (-) battery terminal
      Fig 10: Locating Injector Connectors
      G05749375Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE: When disconnecting the cable, some systems need to be initialized after the cable is reconnected (See INITIALIZATION ).
    24. Clear the DTCs (See DTC CHECK/CLEAR ).
  10. INSPECT CO/HC 

    HINT.

    This check determines whether or not the idle CO/HC complies with regulations

    1. Start the engine
    2. Keep the engine speed at 2500 rpm for approximately 180 seconds.
    3. Insert the CO/HC meter testing probe at least 40 cm (1.3 ft) into the tailpipe during idle
    4. Immediately check CO/HC concentration during idle and when running at 2500 rpm.
      Fig 11: Identifying CO/HC Meter
      G05749380Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT.

      • When performing the 2 mode (with the engine idling/running at 2500 rpm) test, follow the measurement order determined by applicable local regulations
      • If the CO/HC concentration does not comply with the regulations, perform troubleshooting in the order given below
      1. Check the A/F sensor and heated oxygen sensor operation
      2. See the table below for possible causes, then inspect and correct the applicable causes if necessary
      CO/HC SYMPTOM CHART

      CO HC Symptom Cause
      Normal High Rough idle
      1. Misfiring
        • Incorrect timing
        • Plugs are contaminated, shorted, or gaps are incorrect
      2. Leaky intake and exhaust valves
      3. Leaky cylinder
      Low High Rough idle (Fluctuating HC reading)
      1. Vacuum leaks
        • PCV hose
        • Intake manifold
        • Throttle body
      2. Lean mixture causing misfire
      High High Rough idle (Black smoke from exhaust)
      1. Restricted air filter
      2. Faulty SFI system
        • Incorrect pressure
        • Defective ECT sensor
        • Faulty ECM
        • Faulty injector
        • Faulty throttle position sensor
        • Faulty MAF sensor
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