Emission Control System: Inspection

INSPECT VENTILATION VALVE SUB-ASSY
1. Install a clean hose to the ventilation valve.
2. Inspect the ventilation valve operation.
  1. Blow air into the cylinder head side, and check that air passes through easily.
    CAUTION: Do not suck air through the valve. Petroleum substances inside the valve are harmful.
    
    Fig 1: Inspecting Ventilation Valve Sub-Assy
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Blow air into the intake manifold side, and check that air passes through with difficulty.
  If the operation is not as specified, replace the ventilation valve.
3. Remove the clean hose from the ventilation valve.
  
  Fig 2: Inspecting Ventilation Valve Sub-Assy
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT FUEL TANK CAP ASSY
1. Visually check if the cap or gasket is deformed or damaged.
  
  Fig 3: Inspecting Fuel Tank Cap Assy
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT CHARCOAL CANISTER ASSY
1. Visually check the charcoal canister for cracks or damage.
2. Inspect the charcoal canister operation.
  
  Fig 4: Inspecting Charcoal Canister Assy
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Plug the vent port with a cap.
    
    Fig 5: Plugging Vent Port
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. While holding the purge port closed, blow air (1.76 kPa, 18 gf/cm² , 0.26 psi) into the EVAP port and check that air flows from the air inlet port.
  3. Plug the air inlet port with your finger.
    
    Fig 6: Plugging Air Inlet Port
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. Apply vacuum (3.43 kPa, 25.7 mmHg, 1.01 in.Hg), check that the vacuum decreases when the air inlet port is opened.
    
    Fig 7: Applying Vacuum
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. While holding the air inlet port closed, apply vacuum (3.43 kPa, 25.7 mmHg, 1.01 in.Hg) to the EVAP port and check that air flows into the purge port.
    If a problem is found, replace the charcoal canister.
  6. Remove the cap from the vent port.
    
    Fig 8: Applying Vacuum
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Inspect the VSV for open circuit.
  1. Using an Ohmmeter, check the resistance between the terminals.
  Resistance:
  
  Fig 9: Checking VSV Terminals Resistance
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 10: Resistance Reference Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  If the resistance is not as specified, replace the VSV.
4. Inspect the VSV for ground.
  1. Using an ohmmeter, check that there is no continuity between each terminal and the body.
    If there is continuity, replace the VSV.
    
    Fig 11: Inspecting VSV For Ground
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Inspect the VSV operation.
    1. Check that air flows from port A to port B.
      
      Fig 12: Inspecting VSV Operation
      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Apply battery positive voltage across the terminals.
    3. Check that air does not flow from port A to port B. If operation is not as specified, replace the VSV.
  Fig 13: Applying Battery Voltage To VSV
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT DUTY VACUUM SWITCHING VALVE
1. Inspect the VSV for open circuit.
  1. Using an ohmmeter, check resistance between the terminals.
  Resistance:
  
  30 to 34° at 20° C (68° F)
  
  If the resistance is not as specified, replace the VSV.
  
  Fig 14: Checking VSV Terminal Resistance
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Inspect the VSV for ground.
  1. Using an ohmmeter, check that there is no continuity between each terminal and the body.
  If there is continuity, replace the VSV.
  
  Fig 15: Inspecting VSV For Ground
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Inspect the VSV operation.
  1. Check that air flows with difficulty from port E to port F.
    
    Fig 16: Inspecting VSV Operation
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Apply battery voltage across the terminals.
  3. Check that air flows from port E to port F.
    If operation is not as specified, replace the VSV.
Fig 17: Applying Battery Voltage To VSV
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT HEATED OXYGEN SENSOR (BANK 1 OXYGEN SENSOR)
1. Using an Ohmmeter, check for continuity between the terminals.
  Standard:
  
  Fig 18: Identifying Bank 1 Oxygen Sensor Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 19: Reference Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  If result is not as specified, replace the sensor.
INSPECT HEATED OXYGEN SENSOR (BANK 1 OXYGEN SENSOR NO. 2)
1. Using an ohmmeter, check for continuity between the terminals.
  Standard:
  
  Fig 20: Identifying Bank 1 Oxygen Sensor No. 2 Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 21: Reference Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  If result is not as specified, replace the sensor.