Emission Control System: Inspection

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: Installing Clean Hose To Ventilation Valve

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Blow air into the intake manifold side, and check that air passes through with difficulty.

   If operation is not as specified, replace the ventilation valve.

3. Remove the clean hose from the ventilation valve.

Fig 2: Checking Ventilation Valve

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Visually check if the cap and/or gasket are deformed or damaged.

Fig 3: Identifying Gasket

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Visually check the charcoal canister for cracks or damage.
   Fig 4: Checking Charcoal Canister For Cracks Or Damage

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Inspect the charcoal canister operation.
   1. With the purge port closed, blow air (0.39 kPa, 4.0 gf/cm² , 0.06 psi) into the vent port, and check that air flows from the air inlet port.
      Fig 5: Checking Air Flows From Air Inlet Port

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. With the air inlet port closed, blow air (0.39 kPa, 4.0 gf/cm² , 0.06 psi) into the vent port, and check that air flows from the purge port.
      Fig 6: Checking Air Flows From Purge Port

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   3. With the air inlet port closed, apply vacuum (3.43 kPa, 25.7 gf/cm² , 1.01 psi) to the vent port, and check that air is sucked in from the purge port.

   If operation is not as specified, replace the charcoal canister.

   Fig 7: Checking Air Is Sucked In From Purge Port

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Inspect the air tightness.
   1. With the vent and air inlet ports closed, apply vacuum (3.43 kPa, 25.7 gf/cm² , 1.01 psi) to the purge port, and check that the vacuum remains stable for 1 minute.
   Fig 8: Inspecting Air Tightness

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   HINT:

   In order to maintain air tightness, this operation should be performed with the CCV terminal ports closed by your fingers. If operation is not as specified, replace the charcoal canister.

4. Inspect the diaphragm.
   1. Remove the air hose between ports A and B.
   2. With the vent, purge and air inlet ports closed, apply vacuum (1.42 kPa, 11 mmHg, 0.42 in.Hg) into port A, and check that air is sucked in from port B.
      Fig 9: Checking Air Is Sucked In From Port B

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   3. With the vent, purge and air inlet ports closed, apply vacuum (1.42 kPa, 11 mmHg, 0.42 in.Hg) into port A, and measure how long it takes for vacuum to drop.

      Vacuum drop time: 10 sec. or more 

      If operation is not as specified, replace the charcoal canister.

   4. Reinstall the air hose between ports A and B.
   Fig 10: Installing Air Hose Between Ports A & B

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
5. Inspect VSV for open circuit.
   1. Using an ohmmeter, check the resistance between the terminals.

   Resistance: 

   RESISTANCE SPECIFICATIONS
   
   

   20°C (68°F)	25 to 30 Ω
   100°C (212°F)	32 to 42 Ω

   If the resistance is not as specified, replace the charcoal canister.

   Fig 11: Checking Resistance Between Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
6. Inspect VSV operation.
   1. Check that air flows from port A to ports B and C.
      Fig 12: Checking Air Flows From Port A To Ports B & C

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Apply battery positive voltage across the terminals.
   3. Check that the valve is closed.
      Fig 13: Applying Battery Positive Voltage Across Terminals

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   4. Check that air does not flow from port A to port B.
   5. Check that air flows from port A to port C.

   If operation is not as specified, replace the charcoal canister.

Fig 14: Checking Air Flows From Port A To Port C

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Inspect the VSV for open circuit.
   1. Using an ohmmeter, check the resistance between the terminals.

   Resistance: 26 to 30 Ω at 20°C (68°F) 

   If the resistance is not as specified, replace the VSV.

   Fig 15: Checking Resistance Between Terminals

   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 16: Checking Continuity Between Terminal & Body

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Inspect the VSV operation.
   1. Check that air does not flow from the part.
      Fig 17: Checking Air Flow From Part

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Apply battery positive voltage across the terminals.
   3. Check that air flows from the port.

   If operation is not as specified, replace the VSV.

Fig 18: Applying Battery Positive Voltage Across Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Using an ohmmeter, measure the resistance between the terminals.

   Resistance: 

If the resistance is not as specified, replace the sensor.

Fig 19: Identifying Air Fuel Ratio Sensor Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Using an ohmmeter, measure the resistance between the terminals.

   Resistance: 

If the resistance is not as specified, replace the sensor.

Fig 20: Identifying Heated Oxygen Sensor Connector (1 Of 2)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Using an ohmmeter, measure the resistance between the terminals.

   Resistance: 

If the resistance is not as specified, replace the sensor.

Fig 21: Identifying Heated Oxygen Sensor Connector (2 Of 2)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002