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Engine Mechanical (Inspection): Engine: Inspection

  1. INSPECT ENGINE COOLANT 
  2. INSPECT ENGINE OIL 
  3. INSPECT BATTERY 
  4. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSY 
  5. INSPECT SPARK PLUG (See  INSPECTION  ) 
  6. INSPECT V-RIBBED BELT 
    1. Check the V-ribbed belt deflection.
      1. Measure the belt deflection

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

        Fig 1: Inspecting V-Ribbed Belt
        G00755848Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Belt tension
        Fig 2: V-Ribbed Belt Deflection Table
        G00755849Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 3: V-Ribbed Belt Tension Table
    G00755847Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    NOTE:
    • Check the drive belt deflection at the specified point.
    • When installing a new belt, set its tension value as specified.
    • When inspecting the belt which is used over 5 minutes, apply the specification of "Used Belt".
    • When reinstalling the belt which is used over 5 minutes, adjust its deflection and tension to the intermediate value of each specification of "Used Belt".
    • V-ribbed belt tension and deflection should be checked after two revolution 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 OBD II scan tool:
      1. Connect the hand-held tester or OBD II scan tool to the DLC3.
      2. Enter DATA LIST MODE on the hand-held tester or OBD II 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 OBD II scan tool:
      1. Using SST, connect terminals 13 (TC) and 4 (CG) of DLC3.

        SST 09843-18040

        NOTE:
        • Make sure of the terminal numbers before connecting them. Incorrect connections could damage the engine.
        • Turn OFF all electrical systems before connecting the terminals.
          Fig 4: Identifying Terminals 13 (TC) And 4 (CG) Of DLC3
          G00755850Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        • Perform this inspection when the cooling fan motor is turned OFF.
      2. Remove the cylinder head cover No. 2.
      3. Pull out the wire harness as shown in the illustration.
        Fig 5: Pulling Out Wire Harness
        G00755851Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Connect the clip of the timing light to the engine.
        NOTE:
        • Use a timing light which can detect the first signal.
        • After checking, be sure to tape the wire harness.
      5. Inspect ignition timing at idle.

        Ignition timing: 8 to 12° BTDC 

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

        HINT: 

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

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

        Ignition timing: 0 to 14° BTDC 

      8. Confirm that 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 OBD II scan tool:
      1. Connect the hand-held tester or OBD II scan tool to the DLC3.
      2. Enter DATA LIST MODE on the hand-held tester or OBD II scan tool.

        Idle speed: 

        Fig 6: Engine Idle Speed
        G00755852Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:
      • When checking the idle speed, the transmission is in the park or neutral position.
      • Check the idle speed with cooling fan OFF.
      • Switch off all accessories and air conditioning before connecting the hand-held tester or OBD II 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 OBD II scan tool:
      1. Using SST, connect the tachometer test lead to terminal 9 (TAC) of DLC3.

        SST 09843-18040

        Fig 7: Identifying Terminal 9 (TAC) Of DLC3
        G00755853Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Check the idle speed.

      Idle speed: 

      Fig 8: Idle Speed Specifications
      G00755854Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:
      • When checking the idle speed, the transmission is in the park or neutral position.
      • Check the idle speed with cooling fan OFF.
      • Switch off all accessories and air conditioning before connecting the test lead 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 cylinder compression pressure.
      Fig 9: Inspecting Cylinder Compression Pressure
      G00755855Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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

        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 engine speed of 250 RPM or more.
        • Check other cylinder's compression pressure in the same way.
        • This measurement must be done in as short a time 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 check 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 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 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 2,500 RPM.

      HINT: 

      When doing the 2 mode (with the engine is in the idle and 2,500 RPM) test, these procedures may vary according to local rules.

    5. 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 table below for possible causes, and then inspect the applicable causes and repair it if necessary.
    Fig 10: CO/HC Possible Causes Table
    G00755856Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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