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Engine Control System (Service Information): Diagnosis Lexus GS III facelift

Engine Control Systems 12 illustrations ~1864 words

ON-VEHICLE INSPECTION

  1. INSPECT ACCELERATOR PEDAL Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on.< Select the following menu items: Powertrain / Engine and ECT / Data List / Accelerator Position No. 1 and Accelerator Position No. 2. When depressing or releasing the accelerator pedal, check that the values of the Accelerator Position No. 1 and Accelerator Position No. 2 are within the specification. Accelerator Position No. 1 standard voltage Condition Specified Condition Accelerator pedal is released 0.5 to 1.1 V Accelerator pedal is depressed 2.6 to 4.5 V Accelerator Position No. 2 standard voltage Condition Specified Condition Accelerator pedal is released 1.2 to 2.0 V Accelerator pedal is depressed 3.4 to 5.0 V If the result is not as specified, check the accelerator pedal, wire harness or ECM.

Scheme 21

Scheme 21: REMOVAL
Scheme 21: REMOVAL
  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL WARNING: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
  2. REMOVE ACCELERATOR PEDAL Disconnect the accelerator pedal position sensor connector. Remove the 2 bolts and accelerator pedal. NOTE: Avoid physical shock to the accelerator pedal. Do not disassemble the accelerator pedal assembly.

Note. Perform the MAF meter inspection according to the procedures below. Only replace the MAF meter when the MAF value in the Data List (with the engine stopped) is not within the normal operating range or there is foreign matter on the MAF meter platinum hot wire (heater).

  1. INSPECT MASS AIR FLOW METER Read the value using the Techstream (MAF). NOTE: Perform the inspection with the vehicle indoors and on a level surface. Perform the inspection of the MAF meter while it is installed to the air cleaner case (installed to the vehicle). During the test, do not use the exhaust air duct to perform suction on the exhaust pipe. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Select the following menu items: Powertrain / Engine and ECT / Data List / MAF. Wait 30 seconds, and read the values on the Techstream. Standard condition Less than 0.54 g/sec. If the result is not as specified, replace the MAF meter. If the result is within the specified range, inspect the MAF meter See step 1 .

Scheme 22

Scheme 22: REMOVAL
Scheme 22: REMOVAL
  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL WARNING: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
  2. REMOVE COOL AIR INTAKE DUCT SEAL . Refer to «REMOVAL - Step 15»(ref-382704-S06161003072011012800000)
  3. REMOVE ENGINE ROOM SIDE COVER RH . Refer to «REMOVAL - Step 16»(ref-382704-S06161003072011012800000)
  4. REMOVE MASS AIR FLOW METER Disconnect the MAF meter connector. Remove the 2 screws and MAF meter. Remove the O-ring from the MAF meter.

Scheme 23

Scheme 23: INSPECTION
Scheme 23: INSPECTION
  1. INSPECT MASS AIR FLOW METER Perform a visual check for any foreign matter on the platinum hot wire (heater) of the mass air flow meter shown in the illustration. OK There is no foreign material. If the result is not as specified, replace the mass air flow meter.
  1. INSPECT CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY Warm up the engine. Turn the engine switch off. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Select the following menu items: Powertrain / Engine and ECT / Data List / Control the VVT Linear (Bank 1), Control the VVT System (Bank 1), Control the VVT Linear (Bank 2), Control the VVT System (Bank 2), Control the VVT Exhaust Linear (Bank 1) and Control the VVT Exhaust Linear (Bank 2). Specified condition Tester Operation Specified Condition OCV OFF Normal engine speed OCV ON Engine idles roughly or stalls soon after OCV is switched from OFF to ON If the result is not as specified, check the oil control valve and wirings. HINT: Control the VVT System (Bank 1): Command to activate oil control valve of bank 1 (Control range: ON/OFF). Control the VVT System (Bank 2): Command to activate oil control valve of bank 2 (Control range: ON/OFF). Control the VVT Linear (Bank 1): Command to activate exhaust and intake side oil control valves of bank 1 (Control range: Between -128 to 127%). Control the VVT Linear (Bank 2): Command to activate exhaust and intake side oil control valves of bank 2 (Control range: Between -128 to 127%). VVT Exhaust Linear (Bank 1): Command to activate exhaust side oil control valve of bank 1 (Control range: Between -128 to 127%). VVT Exhaust Linear (Bank 2): Command to activate exhaust side oil control valve of bank 2 (Control range: Between -128 to 127%).

Scheme 24

Scheme 24: REMOVAL
Scheme 24: REMOVAL

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Scheme 27

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Scheme 28

Scheme 29

Scheme 29
Scheme 29
  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL WARNING: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
  2. REMOVE COOL AIR INTAKE DUCT SEAL . Refer to «REMOVAL - Step 15»(ref-382704-S06161003072011012800000)
  3. REMOVE ENGINE ROOM SIDE COVER RH . Refer to «REMOVAL - Step 16»(ref-382704-S06161003072011012800000)
  4. REMOVE ENGINE ROOM SIDE COVER LH . Refer to «REMOVAL - Step 17»(ref-382704-S06161003072011012800000)
  5. REMOVE V-BANK COVER . Refer to «REMOVAL - Step 18»(ref-382704-S06161003072011012800000)
  6. REMOVE FRONT UPPER FENDER PROTECTOR LH . Refer to «REMOVAL - Step 4»(ref-382735-S40525517372011012800000)
  7. REMOVE FRONT UPPER FENDER PROTECTOR RH . Refer to «REMOVAL - Step 5»(ref-382735-S40525517372011012800000)
  8. REMOVE FRONT FENDER TO COWL SIDE SEAL LH . Refer to «REMOVAL - Step 8»(ref-382735-S40525517372011012800000)
  9. REMOVE FRONT FENDER TO COWL SIDE SEAL RH . Refer to «REMOVAL - Step 9»(ref-382735-S40525517372011012800000)
  10. REMOVE FRONT WIPER ARM AND BLADE ASSEMBLY LH . Refer to «REMOVAL - Step 6»(ref-382735-S40525517372011012800000)
  11. REMOVE FRONT WIPER ARM AND BLADE ASSEMBLY RH . Refer to «REMOVAL - Step 7»(ref-382735-S40525517372011012800000)
  12. REMOVE COWL TOP VENTILATOR LOUVER SUB-ASSEMBLY . Refer to «REMOVAL - Step 10»(ref-382735-S40525517372011012800000)
  13. DRAIN ENGINE COOLANT . Refer to «REPLACEMENT - Step 5»(ref-382708-S21361285702011012800000)
  14. DISCONNECT NO. 2 VENTILATION HOSE See step 7
  15. REMOVE AIR CLEANER CAP WITH AIR CLEANER HOSE See step 8
  16. REMOVE THROTTLE BODY See step 9
  17. REMOVE INTAKE AIR SURGE TANK . Refer to «REMOVAL - Step 19»(ref-382714-S37151221912011012800000)
  18. REMOVE CAMSHAFT TIMING OIL CONTROL VALVE (for Exhaust Side of Bank 1) Disconnect the oil control valve connector. Remove the bolt and oil control valve. Remove the O-ring from the oil control valve.
  19. REMOVE CAMSHAFT TIMING OIL CONTROL VALVE (for Intake Side of Bank 1) Remove the bolt and V-bank cover bracket. Disconnect the oil control valve connector. Remove the bolt and oil control valve. Remove the O-ring from the oil control valve.
  20. REMOVE CAMSHAFT TIMING OIL CONTROL VALVE (for Intake Side of Bank 2) Disconnect the oil control valve connector. Remove the bolt and oil control valve. Remove the O-ring from the oil control valve.
  21. REMOVE CAMSHAFT TIMING OIL CONTROL VALVE (for Exhaust Side of Bank 2) Disconnect the wiring harness from the bracket. Remove the bolt and bracket. Disconnect the oil control valve connector. Remove the bolt and oil control valve. Remove the O-ring from the oil control valve.

Scheme 30

Scheme 30: INSPECTION
Scheme 30: INSPECTION

Scheme 31

Scheme 31
Scheme 31
  1. INSPECT CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY Measure the resistance between the terminals. Standard resistance 6.9 to 7.9 ohms at 20°C (68°F) If the result is not as specified, replace the oil control valve. Connect the battery's positive (+) lead to terminal 1 and negative (-) lead to terminal 2, and check the movement of the valve. OK Condition Specified Condition Battery positive (+) voltage is applied Valve moves in black arrow direction shown in illustration Battery positive (+) voltage is cut off Valve moves in white arrow direction shown in illustration If the result is not as specified, replace the oil control valve. NOTE: If the valve cannot return properly because of foreign matter, a small pressure leak in the advanced direction may occur and a DTC may be output.

Scheme 32

Scheme 32: INSTALLATION
Scheme 32: INSTALLATION
  1. INSTALL CAMSHAFT TIMING OIL CONTROL VALVE (for Exhaust Side of Bank 2) Apply a light coat of engine oil to a new O-ring and install it to the oil control valve. Install the oil control valve with the bolt. Torque: 10 N*m ( 102 kgf*cm, 7 ft.*lbf) NOTE: Be careful that the O-ring is not cracked or jumped when installing the oil control valve. Connect the camshaft timing oil control valve connector. Install the bracket with the bolt. Torque: 21 N*m ( 214 kgf*cm, 15 ft.*lbf) Connect the wiring harness to the bracket.
  2. INSTALL CAMSHAFT TIMING OIL CONTROL VALVE (for Intake Side of Bank 2) Apply a light coat of engine oil to a new O-ring and install it to the oil control valve. Install the oil control valve with the bolt. Torque: 10 N*m ( 102 kgf*cm, 7 ft.*lbf) NOTE: Be careful that the O-ring is not cracked or jumped when installing the oil control valve. Connect the camshaft timing oil control valve connector.
  3. INSTALL CAMSHAFT TIMING OIL CONTROL VALVE (for Intake Side of Bank 1) Apply a light coat of engine oil to a new O-ring and install it to the oil control valve. Install the oil control valve with the bolt. Torque: 10 N*m ( 102 kgf*cm, 7 ft.*lbf) NOTE: Be careful that the O-ring is not cracked or jumped when installing the oil control valve. Connect the camshaft timing oil control valve connector. Install the V-bank cover bracket with the bolt. Torque: 10 N*m ( 102 kgf*cm, 7 ft.*lbf)
  4. INSTALL CAMSHAFT TIMING OIL CONTROL VALVE (for Exhaust Side of Bank 1) Apply a light coat of engine oil to a new O-ring and install it to the oil control valve. Install the oil control valve with the bolt. Torque: 10 N*m ( 102 kgf*cm, 7 ft.*lbf) NOTE: Be careful that the O-ring is not cracked or jumped when installing the oil control valve. Connect the camshaft timing oil control valve connector.
  5. INSTALL INTAKE AIR SURGE TANK . Refer to «INSTALLATION - Step 3»(ref-382714-S35802909982011012800000)
  6. INSTALL THROTTLE BODY See step 1
  7. INSTALL AIR CLEANER CAP WITH AIR CLEANER HOSE See step 2
  8. CONNECT NO. 2 VENTILATION HOSE See step 3
  9. CONNECT CABLE TO NEGATIVE BATTERY TERMINAL
  10. ADD ENGINE COOLANT . Refer to «REPLACEMENT - Step 6»(ref-382708-S21361285702011012800000)
  11. INSPECT FOR COOLANT LEAK . Refer to «ON-VEHICLE INSPECTION - Step 3»(ref-382732-S02646534692011012800000)
  12. INSTALL COWL TOP VENTILATOR LOUVER SUB-ASSEMBLY . Refer to «INSTALLATION - Step 3»(ref-382735-S02822456132011012800000)
  13. INSTALL FRONT WIPER ARM AND BLADE ASSEMBLY LH . Refer to «INSTALLATION - Step 6»(ref-382735-S02822456132011012800000)
  14. INSTALL FRONT WIPER ARM AND BLADE ASSEMBLY RH . Refer to «INSTALLATION - Step 7»(ref-382735-S02822456132011012800000)
  15. INSTALL FRONT FENDER TO COWL SIDE SEAL LH . Refer to «INSTALLATION - Step 4»(ref-382735-S02822456132011012800000)
  16. INSTALL FRONT FENDER TO COWL SIDE SEAL RH . Refer to «INSTALLATION - Step 5»(ref-382735-S02822456132011012800000)
  17. INSTALL FRONT UPPER FENDER PROTECTOR LH . Refer to «INSTALLATION - Step 9»(ref-382735-S02822456132011012800000)
  18. INSTALL FRONT UPPER FENDER PROTECTOR RH . Refer to «INSTALLATION - Step 10»(ref-382735-S02822456132011012800000)
  19. INSTALL V-BANK COVER . Refer to «INSTALLATION - Step 132»(ref-382704-S21777018532011012800000)
  20. INSTALL ENGINE ROOM SIDE COVER LH . Refer to «INSTALLATION - Step 133»(ref-382704-S21777018532011012800000)
  21. INSTALL ENGINE ROOM SIDE COVER RH . Refer to «INSTALLATION - Step 134»(ref-382704-S21777018532011012800000)
  22. INSTALL COOL AIR INTAKE DUCT SEAL . Refer to «INSTALLATION - Step 135»(ref-382704-S21777018532011012800000)
  23. PERFORM INITIALIZATION Perform initialization Refer to «INITIALIZATION»(ref-382578-S40254115562011012800000) . NOTE: Certain systems need to be initialized after disconnecting and reconnecting the cable from the negative (-) battery terminal.

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