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On-Vehicle Inspection

  1. INSPECT AIR-FUEL RATIO COMPENSATION SYSTEM 

    HINT: 

    The system can be also checked by choosing "DATA MONITOR/O2 SENSOR OUTPUT VOLTAGE" on the hand-held tester monitor.

    Fig 1: Identifying ECM Connector Terminals
    G00754678Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Connect the hand-held tester to terminals 23 (OXL1) and 7 (E1) and to terminals 21 (OXL2) and 7 (E1) of the ECM.
      CAUTION: Connect test leads from the back side of the connector with the ECU connected.
    2. Warm up the heated oxygen sensor at 2,500 RPM of the engine speed for approximately 2 minutes.
    3. Confirm that the voltage varies between 0V and 1V at 2,500 RPM of the engine speed.
      1. OK: The voltage varies more than 8 times in 10 seconds. 
      CAUTION:
      • Perform the check immediately after warming up.
      • If the voltage variation could not be verified, warm up the heated oxygen sensor again.
  2. INSPECT FUEL CUT OFF RPM 
    1. Increase the engine speed to at least 3,500 RPM.
    2. Use a sound scope to check for injector operating sounds.
    3. Check that the operating sounds stop momentarily and then resume when the throttle lever is released.

      HINT: 

      Measure with the A/C OFF.

      1. Fuel return RPM: 1,400 RPM 
      Fig 2: Checking Injector Operating Sound
      G00754679Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. VISUALLY INSPECT HOSES, CONNECTIONS AND GASKETS 
    1. Check for cracks or damage.

      HINT: 

      Separation of the engine oil dipstick, oil filler cap, PCV hose, etc. may cause the engine to run improperly. Disconnection, looseness or cracks in the parts of the air induction system between the throttle body and cylinder head will allow air suction and cause the engine to run improperly.

      Fig 3: Inspecting Hoses, Connections And Gaskets
      G00754680Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. INSPECT EVAP SYSTEM LINE 
    1. Warm up the engine to the normal operating temperature.
    2. Stop the engine.
    3. Connect the vacuum gauge (EVAP control system test equipment vacuum gauge) to the EVAP service port on the purge line.
      Fig 4: Connecting Vacuum Gauge
      G00754681Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. If you have the hand-held tester:

      Force the VSV for EVAP to operate.

      1. Connect the hand-held tester to the DLC3.
      2. Start the engine.
      3. Turn the hand-held tester main switch ON.
      4. Select the Active TEST mode on the hand-held tester to operate the VSV for EVAP.
      Fig 5: Connecting Hand-Held Tester
      G00754682Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. If you have no hand-held tester:

      Force the VSV for EVAP to operate.

      1. Disconnect the VSV for EVAP connector.
      2. Connect the positive (+) and negative (-) leads from the battery to the VSV for EVAP terminals.
      3. Start the engine.
      Fig 6: Connecting Battery To VSV
      G00754683Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Check the vacuum at idle.
      1. Vacuum: Minimum between 0.368 and 19.713 in.Hg (5 to 268 in.Ag) for over 5 seconds 

      HINT: 

      If the vacuum does not change, it can be concluded that the hose connecting the VSV to the service port has come loose or is blocked, or the VSV is malfunctioning.

      Fig 7: Checking Vacuum
      G00754684Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. If you have the hand-held tester:

      Return to the normal VSV for EVAP operation.

      1. Stop the engine.
      2. Disconnect the hand-held tester from the DLC3.
    8. If you have no hand-held tester:

      Return to the normal VSV for EVAP operation.

      1. Stop the engine.
      2. Disconnect the positive (+) and negative (-) leads from the VSV for EVAP terminal.
      3. Reconnect the VSV for EVAP connector.
    9. Disconnect the vacuum gauge from the EVAP service port on the purge line.
    10. Connect a pressure gauge to the EVAP service port on the purge line.
      Fig 8: Connecting Pressure Gauge
      G00754685Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    11. If you have the hand-held tester:

      Force the VSV for CCV to operate.

      1. Connect the hand-held tester to the DLC3.
      2. Turn the ignition switch ON.
      3. Turn the hand-held tester main switch ON.
      4. Use the ACTIVE TEST mode on the hand-held tester to operate the VSV for CCV.
      Fig 9: Connecting Hand-Held Tester
      G00754686Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE: Do not start the engine.

      HINT: 

      If the check is not completed within 10 minutes when the VSV for CCV is ON, the forced closure of the VSV for CCV will be reset.

    12. If you have no hand-held tester:

      Force the VSV for CCV to operate.

      1. Disconnect the VSV for CCV connector.
      2. Connect the positive (+) and negative (-) leads from the battery to the VSV for CCV terminals.
      Fig 10: Connecting Battery To VSV
      G00754687Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    13. Check the pressure.
      1. Add the pressure (13.5 to 15.5 in.Ag) from the EVAP service port.
        1. Pressure: 2 minutes after the pressure is added, the gauge should be over 7.7 to 8.8 in.Ag. 
        Fig 11: Checking Pressure
        G00754688Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT: 

        Pressure cannot be added, it can be concluded that the hose connecting the VSV for the EVAP canister fuel tank has slipped off or the VSV is open.

      2. Check if the pressure decreases when the fuel tank cap is removed while adding pressure.

        HINT: 

        If the pressure does not decrease when the fuel tank cap is removed, then it can be concluded that the hose connecting the service port to the fuel tank is blocked, etc.

        Fig 12: Releasing Pressure
        G00754689Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. If you have the hand-held tester:

        Return to the normal VSV for CCV operation.

        1. Turn ignition switch OFF.
        2. Disconnect the hand-held tester from the DLC3.
      4. If you have no hand-held tester:

        Return to the normal VSV for CCV operation.

        1. Disconnect the positive (+) and negative (-) leads from the VSV for CCV terminals.
        2. Reconnect the VSV for CCV connector.
      5. Disconnect the pressure gauge from the EVAP service port on the purge line.
  5. CHECK AIRTIGHTNESS IN FUEL TANK AND FILLER PIPE 
    1. Disconnect the EVAP line hose from the charcoal canister.
      1. Pinch portion A.
      2. Pull out the connector.
        Fig 13: Identifying EVAP Line Hose
        G00754690Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Pressurize and make the internal pressure in the fuel tank 4kPa (41 gf/cm2 , 0.58 psi).
      4. Check that the internal pressure of the fuel tank can be held for 1 minute.
      5. Check the connected portions of each hose and pipe.
      6. Check the installed parts on the fuel tank and filler pipe.

        If there is abnormality, replace the fuel tank and filler pipe.

      7. Reconnect the EVAP line hose to the charcoal canister.
    Fig 14: Removing EVAP Line Hose
    G00754691Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. INSPECT FUEL CUT OFF VALVE AND FILL CHECK VALVE 
    1. Disconnect the purge line hose, EVAP line hose and air inlet line hose from the charcoal canister.
    2. Holding the air inlet line.
    3. Pressurize 4 kPa (41 gf/cm2 , 0.58 psi) to the purge port and check that there is ventilation through the EVAP line hose.
      Fig 15: Inspecting Fuel Cut Off Valve And Fill Check Valve
      G00754692Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT: 

      Check the fuel volume in the fuel tank if there is no ventilation in step (b). If the fuel is full, the EVAP line vent is closed by a float value of the fill check valve, therefore air cannot pass through the EVAP line hose. Reduce the fuel volume if necessary.

    4. Check if the vent line hose and EVAP line does not clog up.

      If they clog, replace the fuel cut off valve and fill check valve.

    5. Reconnect the purge line hose and EVAP line hose to the charcoal canister.
  7. CHECK AIR INLET LINE 
    1. Disconnect the air inlet line hose from the charcoal canister.
    2. Check that there is ventilation in the air inlet line.
    3. Reconnect the air inlet hose to the charcoal canister.
      Fig 16: Checking Air Inlet Line
      G00754693Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  8. VISUALLY INSPECT HOSES, CONNECTIONS AND GASKETS 
    1. Inspect the power source voltage of the vapor pressure sensor.
      1. Turn the ignition switch ON.
      2. Using a voltmeter, measure the voltage between connector terminals VC and E2 of the wiring harness side.

        Voltage: 4.5 to 5.5 V 

      3. Turn the ignition switch OFF.
    2. Inspect the power output of the vapor pressure sensor.
      1. Turn the ignition switch ON.
        Fig 17: Measuring Voltage
        G00754694Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Remove the fuel tank cap.
      3. Using a voltmeter, measure the voltage between connector terminals PTNK and E2 of the wiring harness side.

        Voltage: 3.0 to 3.6 V 

      4. Reinstall the fuel tank cap.
        Fig 18: Measuring Voltage
        G00754695Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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