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On-Vehicle Inspection [11/2021 - ]: Procedure

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  1. INSPECT ENGINE COOLANT (for Engine) 

    Refer to ON-VEHICLE INSPECTION [11/2021 - ]

  2. INSPECT ENGINE OIL 

    Refer to ON-VEHICLE INSPECTION [11/2021 - 03/2024] , or refer to ON-VEHICLE INSPECTION [03/2024 - ]

  3. INSPECT BATTERY CONDITION 

    Refer to ON-VEHICLE INSPECTION [11/2021 - ]

  4. INSPECT SPARK PLUG 

    Refer to ON-VEHICLE INSPECTION [11/2021 - ]

  5. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 
    1. Remove the air cleaner filter element sub-assembly.
    2. Visually check that the air cleaner filter element sub-assembly is not damaged or excessively oily.

      HINT: 

      • If there is any dirt or clogs in the air cleaner filter element sub-assembly, clean it with compressed air.
      • If any dirt or clogs remain even after cleaning the air cleaner filter element sub-assembly with compressed air, replace it.
    3. Install the air cleaner filter element sub-assembly.
  6. INSPECT V-RIBBED BELT 

    See step  1

  7. INSPECT V-RIBBED BELT TENSIONER ASSEMBLY 
    1. Remove the V-ribbed belt.

      Refer to REMOVAL [11/2021 - ]

    2. Turn the V-ribbed belt tensioner assembly clockwise and counterclockwise and check that it turns smoothly and does not catch.

      HINT: 

      If the V-ribbed belt tensioner assembly does not turn smoothly or catches, replace the V-ribbed belt tensioner assembly.

    3. Install the V-ribbed belt.

      Refer to INSTALLATION [11/2021 - ]

  8. INSPECT VALVE LASH ADJUSTER ASSEMBLY NOISE 
    1. Rev up the engine several times. Check that the engine does not emit unusual noises.
    2. If unusual noises occur, warm up the engine and idle it for 30 minutes or more, then perform the inspection.
    3. If any defects or problems are found during the inspection, perform the valve lash adjuster assembly inspection.

      Refer to PROCEDURE - Step 2

  9. INSPECT IGNITION TIMING 
    NOTE:
    • Check the ignition timing with the cooling fan off.
    • Turn off all electrical systems and the A/C.
    • When checking the ignition timing, the transaxle should be in neutral or park.
    1. Start the engine and run it at idle.
    2. Read the value displayed on the GTS.

      Powertrain > Engine > Data List 

      Tester Display
      Ignition Timing Cylinder #1

      Standard Ignition Timing

      0 to 15° BTDC at idle

    3. Check that the ignition timing advances immediately when the engine speed is increased.
    4. Read the value displayed on the GTS.

      Powertrain > Engine > Active Test 

      Active Test Display
      Activate the TC Terminal
      Data List Display
      Ignition Timing Cylinder #1

      Standard Ignition Timing

      8 to 12° BTDC at idle

  10. INSPECT ENGINE IDLE SPEED 
    NOTE:
    • Check the engine idle speed with the cooling fan off.
    • Turn off all electrical systems and the A/C.
    • When checking the ignition timing, the transaxle should be in neutral or park.
    1. Start the engine and run it at idle.
    2. Read the value displayed on the GTS.

      Powertrain > Engine > Data List 

      Tester Display
      Engine Speed

      Standard Idle Speed

      600 to 700 rpm

  11. INSPECT COMPRESSION 
    NOTE:

    Keep the spark plug holes free of foreign matter when measuring the compression pressure.

    1. Warm up and stop the engine.
    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [11/2021 - 03/2023] , or refer to DTC CHECK / CLEAR [03/2023 - ]

    3. Remove the front fender front splash shield LH.

      Refer to PROCEDURE - Step 8 [11/2021 - 03/2024] , or refer to PROCEDURE - Step 8 [03/2024 - ]

    4. Remove the front fender front splash shield RH.

      Refer to PROCEDURE - Step 9 [11/2021 - 03/2024] , or refer to PROCEDURE - Step 9 [03/2024 - ]

    5. Remove the No. 1 engine under cover.

      Refer to PROCEDURE - Step 10 [11/2021 - 03/2024] , or refer to PROCEDURE - Step 10 [03/2024 - ]

    6. Remove the No. 2 engine under cover assembly.

      Refer to PROCEDURE - Step 1

    7. Disconnect the fuel injector connector (for Port Injection).
      GTY1076388Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    8. Disengage the claw and raise the lock lever to disconnect the No. 6 engine wire connector as shown in the illustration.
      GTY1066097Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Lock Lever
      NOTE:

      Perform this step in order to stop fuel injection and prevent damage to the catalyst due to unburned fuel.

    9. Remove the 4 spark plugs.

      Refer to REMOVAL [11/2021 - ]

      NOTE:

      DTCs will be stored if the inspection is performed with the ignition coil assembly connectors disconnected. Make sure that the ignition coil assembly connectors are connected during the inspection.

    10. Check the cylinder compression pressure.
      1. Insert a compression gauge into the spark plug hole.
        GTY885863Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. While cranking the engine, measure the compression pressure.

        Standard Compression Pressure

        1500 kPa (15.3 kgf/cm2 , 218 psi)

        Minimum Compression Pressure

        1300 kPa (13.3 kgf/cm2 , 189 psi)

        Pressure Difference between Each Cylinder

        200 kPa (2.0 kgf/cm2 , 29 psi) or less

        NOTE:
        • Always use a fully charged battery to obtain an engine speed of 250 rpm or more.
        • Measure the compression pressure as quickly as possible.
      3. If the cylinder compression pressure 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 pressure, the piston rings and/or cylinder bore may be worn or damaged.
        • If the compression pressure stays low, a valve may be stuck or seated improperly, or there may be leaks in the cylinder head gasket.
    11. Install the 4 spark plugs.

      Refer to INSTALLATION [11/2021 - ]

    12. Connect the No. 6 engine wire connector and push down the lock lever to engage the claw as shown in the illustration.
      GTY1066186Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Lock Lever
    13. Connect the fuel injector connector (for Port Injection).
      GTY1076388Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    14. Install the No. 2 engine under cover assembly.

      Refer to PROCEDURE - Step 6

    15. Install the No. 1 engine under cover.

      Refer to PROCEDURE - Step 73

    16. Install the front fender front splash shield LH.

      Refer to PROCEDURE - Step 74

    17. Install the front fender front splash shield RH.

      Refer to PROCEDURE - Step 75

    18. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [11/2021 - 03/2023] , or refer to DTC CHECK / CLEAR [03/2023 - ]

      NOTE:

      After performing the inspection, clear the DTCs and confirm that DTCs are not stored again or that the normal system code is output if using a check wire.

  12. INSPECT CO/HC 

    HINT: 

    This check determines whether or not the idle CO/HC complies with regulations.

    1. Start the engine.
    2. Run the engine speed at 2500 rpm for approximately 180 seconds.
    3. Insert a CO/HC meter testing probe at least 40 cm (1.31 ft.) into the tailpipe during idle.
    4. Immediately check the CO/HC concentration at idle and then at an engine speed of 2500 rpm.

      HINT: 

      When performing a 2 mode test (with the engine idling/running at 2500 rpm), the measurement procedures are determined by applicable local regulations.

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

      1. Check for DTCs.

        Refer to DTC CHECK / CLEAR [11/2021 - 03/2023] , or refer to DTC CHECK / CLEAR [03/2023 - ]

      2. See the following table for possible causes, then inspect the applicable parts and repair them if necessary.
        CO HC Problem Cause
        Normal High Rough idle
        1. Faulty ignition:
          • Incorrect valve timing
          • Fouled, shorted or improperly gapped spark plugs
        2. Incorrect valve clearance (valve lash adjuster assembly)
        3. Leaks in intake or exhaust valves
        4. Leaks in cylinders
        5. Faulty EGR
        Low High Rough idle (Fluctuating HC reading)
        1. Vacuum leaks:
          • PCV hoses
          • Intake manifold
          • Throttle body with motor assembly
        2. Lean mixture causing misfire
        3. Faulty EGR
        High High Rough idle (Black smoke from exhaust)
        1. Restricted air cleaner filter element sub-assembly
        2. Plugged PCV valve
        3. Faulty SFI systems:
          • Fuel pressure regulator assembly
          • Engine coolant temperature sensor
          • Mass air flow meter sub-assembly
          • ECM
          • Fuel injector assemblies
          • Throttle position sensor (built into throttle body with motor assembly)
        4. Faulty EGR
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