2008 Lexus RX 400h FWDFACTORY OEM SERVICE PROCEDURE

Knock Sensor: Removal

  1. DISCHARGE FUEL SYSTEM PRESSURE 

    (See FUEL SYSTEM )

  2. PRECAUTION 

    (See PRECAUTION )

  3. REMOVE ENGINE ROOM SIDE LH COVER NO.2  (See REMOVAL )
  4. REMOVE ENGINE ROOM COVER SIDE  (See REMOVAL )
  5. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL 
  6. DRAIN COOLANT (for Engine)  (See COOLANT (FOR ENGINE) )
  7. REMOVE FRONT WIPER ARM AND BLADE ASSEMBLY RH  (See REMOVAL )
  8. REMOVE FRONT WIPER ARM AND BLADE ASSEMBLY LH  (See REMOVAL )
  9. REMOVE COWL TOP VENTILATOR LOUVER SUB-ASSEMBLY  (See REMOVAL )
  10. REMOVE WINDSHIELD WIPER MOTOR AND LINK ASSEMBLY  (See REMOVAL )
  11. REMOVE COWL TOP PANEL SUB-ASSEMBLY OUTER  (See REMOVAL )
  12. REMOVE COOL AIR INTAKE DUCT SEAL  (See REMOVAL )
  13. REMOVE AIR CLEANER CAP W/ INLET  (See REMOVAL  )
  14. REMOVE AIR CLEANER CASE W/ RESONATOR  (See REMOVAL  )
  15. SEPARATE BRAKE MASTER CYLINDER RESERVOIR SUB-ASSEMBLY  (See REMOVAL )
  16. REMOVE RESERVOIR BRACKET  (See REMOVAL )
  17. REMOVE AIR CLEANER BRACKET  (See REMOVAL )
  18. REMOVE ENGINE MOVING CONTROL ROD  (See REMOVAL )
  19. REMOVE EMISSION CONTROL VALVE SET 
    1. Disconnect the VSV connector (A).
    2. Remove the wire harness clamp (B).
    3. Disconnect the fuel vapor feed hose No. 1 (C).
    4. Disconnect the fuel vapor feed hose No. 2 (D).
    5. Remove the 2 nuts (E), then remove the emission control valve set.
      Fig 1: Locating Emission Control Valve Set Nuts And Fuel Vapor Feed Hose
      G05200256Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  20. REMOVE INTAKE AIR SURGE TANK 
    1. Disconnect the throttle motor connector (A).
    2. Separate the water by-pass hose No. 2 (B).
    3. Separate the water by-pass hose No. 3 (C).
    4. Separate the fuel vapor feed hose (D).
      Fig 2: Identifying Throttle Motor Connector And Water By-Pass Hose
      G05200257Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Disconnect the ventilation hose.
      Fig 3: Locating Ventilation Hose
      G05200258Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Remove the 2 bolts, then remove the engine hanger No.1 (A).
    7. Remove the 2 bolts, then remove the surge tank stay No. 1 (B).
    8. Remove the 2 bolts, then remove the surge tank stay No. 2 (C).
      Fig 4: Locating Engine Hanger No.1 And Bolts
      G05200259Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    9. Disconnect the ground cable connector.
    10. Using a socket hexagon wrench 8 mm, remove the 4 bolts.
    11. Remove the 2 nuts, then remove the emission control valve bracket and the intake air surge tank.
    12. Remove the gasket from the intake air surge tank.
      Fig 5: Identifying Ground Cable Connector
      G05200260Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  21. DISCONNECT FUEL PIPE SUB-ASSEMBLY 
    1. Remove the EFI fuel pipe clamp No.1.
    2. Pinch the quick connector and then pull out the fuel pipe No. 1.
      NOTE:
      • Remove dirt or foreign objects on the quick connector before this work.
      • Do not to allow any scratches or foreign objects on the parts when disconnecting as the fuel hose connector has the O-ring that seals the pipe.
      • Perform this work by hand. Do not use any tools.
      • Do not forcibly bend, twist or turn the nylon tube.
      • Protect the connected part by covering it with a vinyl bag after disconnecting the hose.
      • If the quick connector and pipe are stuck, push and pull them to release.
        Fig 6: Identifying Quick Connector And EFI Fuel Pipe Clamp No.1
        G05275803Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  22. DISCONNECT HEATER WATER INLET HOSE 
    1. Disconnect the heater water inlet hose.
      Fig 7: Locating Heater Water Inlet Hose
      G05200262Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  23. DISCONNECT RADIATOR HOSE INLET 
    1. Disconnect the radiator hose inlet.
      Fig 8: Locating Radiator Hose Inlet
      G05200272Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  24. REMOVE INTAKE MANIFOLD 
    1. Remove the nut and ground cable.
      Fig 9: Locating Nut And Ground Cable
      G05200264Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the 6 fuel injector connectors.
      Fig 10: Locating Fuel Injector Connectors
      G05275807Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. In order to remove the intake manifold, using several steps, remove the 9 bolts and 2 nuts in the sequence shown in the illustration.
      4. Fig 11: Identifying Intake Manifold Nuts Removing Sequence
      G05200266Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  25. REMOVE WATER OUTLET  (See REMOVAL )
  26. REMOVE KNOCK CONTROL SENSOR 
    1. Disconnect the 2 knock sensor connectors.
    2. Remove the 2 nuts, and then remove the 2 knock sensors.
      Fig 12: Locating Knock Sensor Connectors And Nuts
      G05200267Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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