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Engine Performance: Tune-Up: Engine: Engine: Inspection

  1. INSPECT ENGINE COOLANT (See  COOLING SYSTEM  ) 
  2. INSPECT ENGINE OIL (See  LUBRICATION SYSTEM  ) 
  3. INSPECT BATTERY
  4. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSY 
  5. INSPECT SPARK PLUG (See  INSPECTION  ) 
  6. INSPECT V-RIBBED BELT 
    Fig 1: Measuring Belt Deflection And Tension
    G00758846Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the V-ribbed belt deflection.
      1. Measure the belt deflection.

        Pressing force: 98 N (10 kgf, 22lbf)

        Fig 2: V-Ribbed Belt Deflection Specifications
        G00758847Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Tension
        Fig 3: V-Ribbed Belt Tension Specifications
        G00758848Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    NOTE:
    • Check the drive belt deflection at the specified point.
    • When installing a new belt, set its tension as specified value.
    • When inspecting the belt which is used for over 5 minutes, apply the specification of "Used Belt".
    • When reinstalling the belt which is used for over 5 minutes, adjust its deflection and tension to the intermediate value in each specification of "Used Belt".
    • V-ribbed belt tension and deflection should be checked after two revolutions of engine cranking.
    • When using a belt tension gauge, confirm the accuracy by using a master gauge first.
  7. INSPECT IGNITION TIMING 
    1. Warm up the engine.
    2. When using the hand-held tester or OBDII scan tool.
      1. Connect the hand-held tester or OBDII scan tool to the DLC3.
      2. Enter DATA LIST MODE on the hand-held tester or OBDII scan tool.

      Ignition timing: 8 to 12° BTDC 

      HINT: 

      Please refer to the hand-held tester operator's manual if you need help to select DATA LIST.

    3. When not using the hand-held tester or OBDII scan tool:
      1. Using SST, connect terminals 13 (TC) and 4 (CG) of DLC3.

        SST 09843-18040

        Fig 4: Identifying Terminals
        G00758849Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        NOTE:
        • Make sure of the terminal numbers before connecting them. Connection with a wrong terminal can damage the engine.
        • Turn OFF all electrical systems before connecting the terminals.
        • Perform this inspection after the cooling fan motor is turned OFF.
      2. Remove the cylinder head cover No. 2.
      3. Pull out the wire as shown in the illustration.
      4. Connect the tester terminal of the timing light to the pulled-out wire.
        Fig 5: Pulling Out Wire
        G00758850Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        NOTE:
        • Use a timing light which detects the first signal.
        • After checking, be sure to wrap the wire harness with tape.
      5. Inspect the ignition timing at idle.

        Ignition timing: 8 to 12° BTDC 

        NOTE: When checking the ignition timing, shift the transmission to the neutral or parking position.

        HINT: 

        Run the engine at 1,000 to 1,300 RPM for 5 seconds, check that the engine RPM returns to the idle speed.

      6. Disconnect terminals 13 (TC) and 4 (CG) of the DLC3.
      7. Inspect the ignition timing at idle.

        Ignition timing: 0 to 14° BTDC 

      8. Confirm that the ignition timing advances when the engine RPM is increased.
      9. Remove the timing light.
  8. INSPECT ENGINE IDLE SPEED 
    1. Warm up the engine.
    2. When using the hand-held tester or OBDII scan tool:
      1. Connect the hand-held tester or OBDII scan tool to the DLC3.
      2. Enter DATA LIST MODE on the hand-held tester or OBDII scan tool.

      Idle speed: 

      Fig 6: Idle Speed Table
      G00758851Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:
      • When checking the idle speed, the transmission is in the neutral or parking position.
      • Check the idle speed with the cooling fan OFF.
      • Switch off all accessories and air conditioning before connecting the hand-held tester or OBDII scan tool.

      HINT: 

      Please refer to the hand-held tester operator's manual if you need help to select DATA LIST.

    3. When not using the hand-held tester or OBDII scan tool:
      1. Using SST, connect the tachometer test prove to terminal 9 (TAC) of the DLC3.

        SST 09843-18040

      2. Check the idle speed.

      Idle speed: 

      Fig 7: Idle Speed Table
      G00758852Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 8: Identifying Terminal
      G00758853Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:
      • When checking the idle speed, the transmission is in the neutral or parking position.
      • Check idle speed with the cooling fan OFF.
      • Switch off all accessories and air conditioning before connecting the test prove to the terminal.
  9. INSPECT COMPRESSION 
    1. Warm up and stop the engine.
    2. Disconnect the injector connectors.
    3. Remove the ignition coils.
    4. Remove the spark plugs.
    5. Inspect the cylinder compression pressure.
      1. Insert a compression gauge into the spark plug hole.
      2. Fully open the throttle.
      3. While cranking the engine, measure the compression pressure.

        SST 09992-00500

        Fig 9: Inspecting Cylinder Compression Pressure
        G00758854Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Compression pressure: 

        1,471 kPa (15.0 kgf/cm 2, 213 psi) 

        Minimum pressure: 

        1,079 kPa (11.0 kgf/cm 2, 156 psi) 

        Difference between each cylinder: 

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

        NOTE:
        • Always use a fully charged battery to obtain the engine speed of 250 RPM or more.
        • Check other cylinder's compression pressure in the same way.
        • This measurement must be done as shortly 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 it again.

      HINT: 

      • If adding oil increases the compression, the piston rings and/or cylinder bore may be worn or damaged. 
      • If the pressure stays low, a valve may be sticking or seating improperly, or there may be leakage past the gasket. 
  10. INSPECT CO/HC 
    1. Start the engine.
    2. Run the engine at 2,500 RPM for approximately 180 seconds.
    3. Insert the CO/HC meter testing probe at least 40 cm (1.3 ft) into the tailpipe during idling.
    4. Immediately check the CO/HC concentration at idle and 2,500 RPM.

    HINT: 

    When doing the 2 mode (with the engine is at idle and 2,500 RPM) test, these measuring orders are 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 INSPECTION ).
    2. See the Fig 10 below for possible causes, and then inspect the applicable causes and repair it if necessary.
      Fig 10: Possible Causes Table
      G00758855Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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