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Engine Adjustment: Adjustment

  1. INSPECT COOLANT, see  ON-VEHICLE INSPECTION  . 
  2. INSPECT ENGINE OIL, see  ON-VEHICLE INSPECTION  . 
  3. INSPECT BATTERY SPECIFIC GRAVITY, see  ON-VEHICLE INSPECTION  . 
  4. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 
  5. INSPECT FAN AND GENERATOR V BELT 
    NOTE: Use of the automatic tensioner has made the tension and flexibility measurements unnecessary.
    1. Check that the indicator mark on the automatic tensioner is within the A range as shown in the illustration.
    2. When the mark is out of the standard range, exchange the V belt with new one.
    Fig 1: Identifying Fan And Generator V Belt Wear Range
    G03387217Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. INSPECT V-RIBBED BELT TENSIONER ASSEMBLY, see  MANUFACTURER'S SUGGESTED SCHEDULED MAINTENANCE  . 
  7. WARM UP ENGINE 
  8. INSPECT IGNITION TIMING 
    1. When using LEXUS hand-held tester:
      1. Connect a LEXUS hand-held tester to the DLC3.
      2. Please refer to the LEXUS hand-held tester operator's manual for further details.
      3. Start the engine at idle.
        Fig 2: Connecting Lexus Hand-Held Tester To DLC3
        G03387218Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Using a timing light, check the ignition timing.

        Ignition timing: 8 - 12° BTDC @ idle 

        (Transmission in neutral position) 

      5. Disconnect the LEXUS hand-held tester from the DLC3.
        Fig 3: Checking Ignition Timing
        G03387219Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. When not using LEXUS hand-held tester:
      1. Using SST, connect tachometer probe to terminal TAC of the DLC3.

        SST 09843-18030

        Fig 4: Connecting Tachometer Probe To Terminal TAC Of DLC3
        G03387220Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Connect the tester probe of a timing light to the yellow lead wire of the ignition coil connector for No. 1 cylinder.
        Fig 5: Connecting Tester Probe Of Timing Light To Yellow Lead Wire
        G03387221Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Using SST, connect terminals TC and CG of the DLC3.

        SST 09843-18040

        Fig 6: Connecting Terminals TC And CG Of DLC3
        G03387222Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Using a timing light, check the ignition timing.

        Ignition timing: 8 - 12° BTDC @ idle 

        (Transmission in neutral position) 

      5. Remove the SST from the DLC3.
      6. Disconnect the timing light from the engine.
      7. Disconnect the tachometer from the DLC3.
  9. INSPECT ENGINE IDLE SPEED 
    1. When using LEXUS hand-held tester:
      1. Connect a LEXUS hand-held tester to the DLC3.
      2. Please refer to the LEXUS hand-held tester operator's manual for further details.
      3. Race the engine at 2,500 RPM for approx. 90 seconds.
      4. Check the idle speed.

        Idle speed (w/Cooling fan OFF): 750 +/- 50 RPM 

      5. Disconnect the LEXUS hand-held tester from the DLC3.
      Fig 7: Inspecting Engine Idle Speed Using Lexus Hand-Held Tester
      G03387223Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. When not using LEXUS hand-held tester:
      1. Using SST, connect tachometer probe to terminal TAC of the DLC3.

        SST 09843-18030

      2. Please refer to the LEXUS hand-held tester operator's manual for further details.
      3. Race the engine at 2,500 RPM for approx. 90 seconds.
      4. Check the idle speed.

        Idle speed (w/Cooling fan OFF): 750 +/- 50 RPM 

      5. Remove the SST from the DLC3.
      6. Disconnect the tachometer from the DLC3.
    Fig 8: Inspecting Engine Idle Speed Using Tachometer
    G03387224Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  10. INSPECT COMPRESSION 
    1. Remove the V-bank cover.
    2. Remove the air cleaner inlet and intake air pipe.
    3. Disconnect the throttle control motor connector.
    4. Remove the oil level gauge guide.
    5. Remove the 8 ignition coils.
    6. Remove the 8 spark plugs. I
    7. Disconnect the 8 injector connectors.
    8. Inspect the cylinder compression pressure.
      1. Insert a compression gauge into the spark plug hole.
      2. Fully open the throttle forcibly by hand.
      3. While cranking the engine, measure the compression pressure.
        Fig 9: Inspecting Cylinder Compression
        G03387225Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        NOTE: Always use a fully charged battery to obtain engine speed of 250 RPM or more.
      4. Repeat steps (1) through (3) for each cylinder.
        NOTE: This measurement must be done in as short a time as possible.

        Compression pressure: 

        1,226 kPa (12.5 kgf/cm 2  , 178 psi) or more 

        Minimum pressure: 981 kPa (10.0 kgf/cm 2  , 142 psi) 

        Difference between each cylinder: 

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

      5. If the cylinder compression in one or more cylinders is low, pour a small amount of engine oil into the cylinder through the spark plug hole and repeat steps (a) through (c) for cylinders with low compression.
        • If adding oil helps the compression, it is likely that the piston rings and/or cylinder bore are worn or damaged.
        • If pressure stays low, a valve may be sticking or seating is improper, or there may be leakage past the gasket.
    9. Connect the 8 injector connectors.
    10. Install the 8 spark plugs.
    11. Install the 8 ignition coils.
    12. Install the oil level gauge guide.
    13. Connect the throttle control motor connector.
    14. Install the air cleaner inlet and intake air pipe.
    15. Install the V-bank cover.
  11. INSPECT CO/HC 

    HINT:

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

    1. Start engine.
    2. Hold the engine at 2,500 RPM for approx. 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/or 2,500 RPM.
      NOTE:
      • Complete the measuring within 3 minutes.
      • When performing the 2 mode (2,500 RPM and idle) test, follow the measurement order 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 DTC P0135, DTC P0141, DTC P0155 OR DTC P0161 and DTC P0136 OR DTC P0156: HEATED OXYGEN SENSOR .
      2. See the PROBLEM SYMPTOMS (CO/HC)  table.
    PROBLEM SYMPTOMS (CO/HC)

    CO HC Symptom Causes
    Normal High Rough idle
    1. Faulty ignitions:
      • Incorrect timing
      • Fouled, shorted or improperly gapped plugs
    2. Incorrect valve clearance
    3. Leaky intake and exhaust valves
    4. Leaky cylinder
    Low High Rough idle (HC reading fluctuating)
    1. Vacuum leaks:
      • PCV hose
      • Intake manifold
      • Throttle body
    2. Lean mixture causing misfire
    High High Rough idle (Black smoke from exhaust)
    1. Restricted air filter
    2. Faulty SFI system:
      • Faulty pressure regulator
      • Defective ECT sensor
      • Faulty ECM
      • Faulty injector
      • Faulty throttle position sensor
      • MAF sensor
  12. DRIVING TEST