ENGINE ON-VEHICLE INSPECTION


  1. INSPECT IGNITION TIMING

    Note


    • Turn all electrical systems off.


    • Perform the inspection when the cooling fan motor is turned off.


    1. Warm up the engine.

    2. When using the intelligent tester:


      1. Connect the intelligent tester to the DLC3.

      2. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / IGN Advance.

      3. Inspect the ignition timing during idling.

        Standard ignition timing
        8 to 12° BTDC @ idle (transmission in neutral and A/C switch off)

      4. Check that the ignition timing advances immediately when the engine speed is increased.

    3. A00OA3ME05

      When not using the intelligent tester:


      1. Using SST, connect terminals 13 (TC) and 4 (CG) of the DLC3.

        SST
        09843-18040
        Text in Illustration
        *a Front view of DLC3

        Note

        Be sure not to improperly connect the terminals. This may damage the engine.

      2. Connect the tester probe of a timing light to the wire of the ignition coil connector for the No. 1 cylinder.

        Note


        • Use a timing light that detects primary signals.


        • After the inspection, be sure to wrap the wire harness with tape.

      3. A00OB71E01

        Inspect the ignition timing during idling.

        Standard ignition timing
        8 to 12° BTDC @ idle (transmission in neutral and A/C switch off)

      4. Remove SST from the DLC3.

      5. Inspect the ignition timing during idling.

        Standard ignition timing
        7 to 24° BTDC @ idle (transmission in neutral and A/C switch off)

      6. Disconnect the timing light from the engine.

  2. INSPECT ENGINE IDLE SPEED

    Note


    • Turn all the electrical systems off.


    • Perform the inspection when the cooling fan motor is turned off.


    1. Warm up the engine.

    2. When using the intelligent tester:


      1. Connect the intelligent tester to the DLC3.

      2. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Engine Speed.

      3. Inspect the engine idle speed.

        Standard idle speed
        690 to 790 rpm (transmission in neutral and A/C switch off)
    3. A00OA3ME06
      Text in Illustration
      *a Front view of DLC3

      When not using the intelligent tester:


      1. Connect SST to terminal 9 (TAC) of the DLC3.

        SST
        09843-18040

      2. Race the engine at 2500 rpm for approximately 90 seconds.

      3. Inspect the engine idle speed.

        Standard idle speed
        690 to 790 rpm (transmission in neutral and A/C switch off)

  3. INSPECT COMPRESSION


    1. Warm up and stop the engine.

    2. Remove the intake air surge tank Click here.

    3. Remove the 6 spark plugs Click here.

    4. Disconnect the 6 fuel injector connectors.

    5. Inspect the cylinder compression pressure.


      1. Insert a compression gauge into the spark plug hole. (Procedure A)

      2. While cranking the engine, measure the compression pressure. (Procedure B)

        Compression pressure
        1400 kPa (14.3 kgf/cm2, 203 psi) or higher
        Minimum pressure
        1100 kPa (11.2 kgf/cm2, 160 psi)
        Difference between each cylinder
        100 kPa (1.0 kgf/cm2, 15 psi) or less

        Tech Tips


        • Use a fully-charged battery so that the engine speed can be increased to 250 rpm or more.

        • Measure the compression in as short a time as possible.

      3. Repeat procedures A and B for each cylinder.

      4. If the cylinder compression is low, pour a small amount of engine oil into the cylinder through the spark plug hole and repeat procedures A and B for cylinders with low compression.


        • 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 from the gasket.

    6. Connect the 6 injector connectors.

    7. Install the 6 spark plugs Click here.

    8. Install the intake air surge tank Click here.

  4. INSPECT CO/HC

    Tech Tips

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


    1. Start the engine.

    2. Run the engine at 2500 rpm for approximately 180 seconds.

    3. Insert the CO/HC meter testing probe at least 40 cm (1.31 ft) into the tailpipe during idling.

    4. Immediately check the CO/HC concentration during idling and/or at 2500 rpm.

      Tech Tips

      When carrying out the 2 tests (idling and 2500 rpm), the measurement orders are prescribed by the applicable local regulations.

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


      1. Check the A/F sensor operation Click here and heated oxygen sensor operation Click here.

      2. See the table below for possible causes, and then inspect and correct the corresponding causes if necessary.

        CO HC Symptom Causes
        Normal High Rough idling

        1. Faulty ignition:


          • Incorrect timing

          • Plugs are contaminated or shorted, or plug gaps are incorrect

        2. Incorrect valve clearance

        3. Leaky intake and exhaust valves

        4. Leaky cylinders
        Low High

        Rough idling

        (Fluctuating HC reading)

        1. Vacuum leaks:


          • Ventilation hoses

          • Intake manifold

          • Throttle body

        2. Lean mixture causing misfire
        High High

        Rough idle

        (Black smoke from exhaust)

        1. Restricted air filter

        2. Plugged PCV valve

        3. Faulty SFI system:


          • Faulty pressure regulator

          • Defective engine coolant temperature sensor

          • Faulty mass air flow meter

          • Faulty ECM

          • Faulty injectors

          • Faulty throttle position sensor