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Section 340 (Engine Mechanical): Engine: Adjustment

WARNING: This page is about a different car, the 2004 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT COOLANT (See  ON-VEHICLE INSPECTION  ) 
  2. INSPECT ENGINE OIL (See  ON-VEHICLE INSPECTION  ) 
  3. INSPECT BATTERY SPECIFIC GRAVITY (See  GENERATORS & REGULATORS  ) 
  4. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSY 
  5. INSPECT FAN AND GENERATOR V BELT 

    HINT:

    Use of the automatic tensioner has made the tension and flexibility measurements unnecessary.

    1. Check that the indicator mark on the automatic tensioner is within the A range as shown in Fig 1.
    2. When the mark is out of the standard range, exchange the V belt with new one.
      Fig 1: Checking Whether Indicator Mark On Automatic Tensioner Is Within Range
      G00926454Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. INSPECT V-RIBBED BELT TENSIONER ASSY (See  REPLACEMENT  ) 
  7. WARM UP ENGINE 
  8. INSPECT IGNITION TIMING 
    1. When using LEXUS hand-held tester:
      1. Connect a LEXUS hand-held tester to the DLC3.
      2. Please refer to the LEXUS hand-held tester operator's manual for further details.
      3. Start the engine at idle.
        Fig 2: Connecting LEXUS Hand-Held Tester To DLC3
        G00926455Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Using a timing light, check the ignition timing.

        Ignition timing: 8-12° BTDC @ idle 

        Fig 3: Checking Ignition Timing
        G00926456Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        (Transmission in neutral position) 

      5. Disconnect the LEXUS hand-held tester from the DLC3.
    2. When not using LEXUS hand-held tester:
      1. Using SST, connect tachometer probe to terminal TAC of the DLC3.

        SST 09843-18030

        Fig 4: Connecting Tachometer Probe To Terminal TAC Of DLC3
        G00926457Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Connect the tester probe of a timing light to the yellow lead wire of the ignition coil connector for No. 1 cylinder.
        Fig 5: Connecting Tester Probe Of Timing Light To Yellow Lead Wire Of Ignition Coil Connector For No. 1 Cylinder
        G00926458Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Using SST, connect terminals TC and CG of the DLC3.

        SST 09843-18040

        Fig 6: Connecting Terminals TC & CG Of DLC3
        G00926459Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Using a timing light, check the ignition timing.

        Ignition timing: 8 - 12° BTDC @ idle 

        (Transmission in neutral position) 

      5. Remove the SST from the DLC3.
      6. Disconnect the timing light from the engine.
      7. Disconnect the tachometer from the DLC3.
    3. 9. INSPECT ENGINE IDLE SPEED 
      1. When using LEXUS hand-held tester:
        1. Connect a LEXUS hand-held tester to the DLC3.
        2. Please refer to the LEXUS hand-held tester operator's manual for further details.
        3. Race the engine at 2,500 rpm for approx. 90 seconds.
        4. Check the idle speed.

          Idle speed (w/ Cooling fan OFF): 750 +/- 50 rpm 

        5. Disconnect the LEXUS hand-held tester from the DLC3.
          Fig 7: Inspecting Engine Idle Speed
          G00926460Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. When not using LEXUS hand-held tester:
        1. Using SST, connect tachometer probe to terminal TAC of the DLC3.

          SST 09843-18030

          Fig 8: Connecting Tachometer Probe To Terminal TAC Of DLC3
          G00926461Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        2. Please refer to the LEXUS hand-held tester operator's manual for further details.
        3. Race the engine at 2,500 rpm for approx. 90 seconds.
        4. Check the idle speed.

          Idle speed (w/ Cooling fan OFF): 750 +/- 50 rpm 

        5. Remove the SST from the DLC3.
        6. Disconnect the tachometer from the DLC3.
    4. 10. INSPECT COMPRESSION 
      1. Remove the V-bank cover.
      2. Remove the air cleaner inlet and intake air pipe.
      3. Disconnect the throttle control motor connector.
      4. Remove the oil level gauge guide.
      5. Remove the 8 ignition coils.
      6. Remove the 8 spark plugs.
      7. Disconnect the 8 injector connectors.
      8. Inspect the cylinder compression pressure.
        1. Insert a compression gauge into the spark plug hole.
        2. Fully open the throttle forcibly by hand.
        3. While cranking the engine, measure the compression pressure.
          Fig 9: Measuring Compression Pressure
          G00926462Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

          HINT:

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

        4. Repeat steps ( 1) through ( 3) for each cylinder.
          NOTE: This measurement must be done in as short a time as possible. 

          Compression pressure: 

          1,226 kPa (12.5 kgf/cm 2  , 178 psi) or more 

          Minimum pressure: 981 kPa (10.0 kgf/cm 2  , 142 psi) 

          Difference between each cylinder: 

          98 kPa (1.0 kgf/cm 2  , 14 psi) or less 

        5. If the cylinder compression in one or more cylinders is low, pour a small amount of engine oil into the cylinder through the spark plug hole and repeat steps ( a) through ( c) for cylinders with low compression.
          • If adding oil helps 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 sticking or seating is improper, or there may be leakage past the gasket.
      9. Connect the 8 injector connectors.
      10. Install the 8 spark plugs.
      11. Install the 8 ignition coils.
      12. Install the oil level gauge guide.
      13. Connect the throttle control motor connector.
      14. Install the air cleaner inlet and intake air pipe.
      15. Install the V-bank cover.
    5. 11. INSPECT CO/HC 

      HINT:

      This check is used only to determine whether or not the idle CO/HC complies with regulations.

      1. Start engine.
      2. Hold the engine at 2,500 rpm for approx. 180 seconds
        Fig 10: Inspecting CO/HC
        G00926463Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Insert CO/HC meter testing probe at least 40 cm (1.3 ft) into tailpipe during idling.
      4. Immediately check CO/HC concentration at idle and/or 2,500 rpm.

      HINT:

      • Complete the measuring within 3 minutes.
      • When performing the 2 mode (2,500 rpm and idle) test, follow the measurement order prescribed by the applicable local regulations.

      If the CO/HC concentration does not comply with regulations, troubleshoot in the order given below.

      1. Check the heated oxygen sensor operation (See DTC P0130, P0150, P2195, P2196, P2197, P2198 , DTC P0133 AND P0153 , DTC P0134 AND P0154 , DTC P0136 AND P0156 ).
      2. See the Fig 11 for possible causes, then inspect and correct the applicable causes if necessary.
        Fig 11: Checking Heated Oxygen Sensor Operation
        G00926464Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  9. DRIVING TEST 
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