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Engine Mechanical: Inspection

  1. INSPECT ENGINE COOLANT (See  REPLACEMENT  ) 
  2. INSPECT ENGINE OIL (See  REPLACEMENT  ) 
  3. INSPECT BATTERY (SEE  GENERATOR ASSY  ) 
  4. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSY 
  5. INSPECT SPARK PLUG (See  INSPECTION  ) 
  6. INSPECT FAN AND GENERATOR V BELT 

    HINT:

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

    1. Check that the indicator mark on the automatic tensioner is within range A as shown in the illustration.
    2. When the mark is out of the standard range, replace the V belt with a new one.
      Fig 1: Inspecting Generator And V Belt
      G01029102Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    HINT:

    • After installing the V belt, check that it fits properly in the ribbed grooves. Check with your hand to confirm that the belt has not slipped out of the groove on the bottom of the crank pulley.
    • A "new belt" is a belt which has been used for less than 5 minutes on a running engine.
    • A "used belt" is a belt which has been used on a running engine for 5 minutes or more.
    • After installing a new belt, run the engine for approximately 5 minutes and then recheck the tension.
      Fig 2: Identifying V Belt
      G01029103Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. INSPECT IGNITION TIMING 
    1. Warm up the engine.
    2. Check the ignition timing.
      1. Connect the hand-held tester (with CAN VIM) to the DLC3.
      2. Enter DATA LIST MODE on the hand-held tester.

        Ignition timing 8 to 12° BTDC @ idle 

    HINT:

    Please refer to the hand-held tester operator manual for help on selecting the DATA LIST.

    Fig 3: Connecting Hand-Held Tester With DLC3
    G01029104Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  8. INSPECT ENGINE IDLE SPEED 
    1. Warm up the engine.
    2. Check the idle speed.
      1. Connect the hand-held tester (with CAN VIM) to the DLC3.
      2. Enter DATA LIST MODE on the hand-held tester.

        Idle speed: 700 to 800 RPM 

        Fig 4: Connecting Hand-Held Tester With DLC3
        G01029105Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:
      • When checking the idle speed, the transmission should be in the neutral position.
      • Check the idle speed with the cooling fan off.
      • Switch off all accessories and A/C before connecting the hand-held tester.

      HINT:

      Please refer to the hand-held tester operator manual for further details.

  9. 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 spark plugs.
    7. Disconnect the 8 injector connectors.
      Fig 5: Identifying Compression Gauge
      G01029106Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    8. Check the cylinder compression pressure.

      SST 09992-00500

      1. Insert a compression gauge into the spark plug hole.
      2. Fully open the throttle.
      3. While cranking the engine, measure the compression pressure.

        Compression pressure: 

        1.2 MPa (12.5 kgf/cm 2  ,178 psi) 

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

        Difference between each cylinder: 

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

        NOTE:
        • Always use a fully charged battery to obtain engine speed of 250 RPM or more.
        • Check other cylinder's compression pressure in the same way.
        • This measurement must be done as quickly as possible.
      4. If the cylinder compression is low, pour a small amount of engine oil into the cylinder through the spark plug hole and inspect again.

      HINT:

      • If adding oil increases the compression, the piston rings and/or cylinder bore may be worn or damaged.
      • If pressure stays low, a valve may be stuck or seated improperly, or there may be leakage in the gasket.
    9. Connect the 8 injector connectors.
    10. Install the 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.
  10. INSPECT CO/HC 
    1. Start the engine.
    2. Rev the engine at 2,500 RPM for approximately 180 seconds.
    3. Insert CO/HC meter testing probe at least 40 cm (1.3 ft) into the tailpipe during idling.
    4. Check CO/HC concentration at idle and/or 2,500 RPM.
      Fig 6: Connecting CO/HC Meter
      G01029107Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      • Complete the measuring within 3 minutes.
      • Check regulations and restrictions in your area when performing 2 mode CO/HC concentration testing (engine check at both idle speed and at 2,500 RPM).
    5. If the CO/HC concentration does not comply with regulations, troubleshoot in the order given below.
      1. Check heated oxygen sensor operation (see DTC P0130 OXYGEN SENSOR CIRCUIT (BANK 1 SENSOR 1), DTC P0150 OXYGEN SENSOR CIRCUIT (BANK 2 SENSOR 1), DTC P2195 OXYGEN SENSOR SIGNAL STUCK LEAN (BANK 1 SENSOR 1), DTC P2196 OXYGEN SENSOR SIGNAL STUCK RICH (BANK 1 SENSOR 1), DTC P2197 OXYGEN SENSOR SIGNAL STUCK LEAN (BANK 2 SENSOR 1), DTC P2198 OXYGEN SENSOR SIGNAL STUCK RICH (BANK 2 SENSOR 1) and see DTC P0133 OXYGEN SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 1), DTC P0153 OXYGEN SENSOR CIRCUIT SLOW RESPONSE (BANK 2 SENSOR 1) ).
      2. See the Fig 7 on the next page for possible causes, and then inspect and repair.
Fig 7: Symptom Chart
G01029108Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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