Emission Control System (1ZZ-FE (Ff)): Inspection

1. Check the operation.
   1. Install a clean hose as shown in the illustration.
   2. Blow air into the cylinder head side, and check that the air passes through easily.
      CAUTION: Do not suck air through the ventilation valve. Petroleum substances Inside the ventilation valve are harmful.
      Fig 1: Checking Air Passes Through Ventilation Valve

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   3. Blow air into the intake manifold side, and check that the air does not pass through freely.

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

      Fig 2: Checking Air Does Not Passes Through Ventilation Valve

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Check the appearance.
   1. Visually check whether the fuel tank cap and gasket are deformed or damaged.

      If necessary, repair or replace the cap and/or gasket.

      Fig 3: Checking Fuel Tank Cap And Gasket

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Visually check the charcoal canister for cracks or damage.

   If cracks or damage are found, replace the charcoal canister assy.

   Fig 4: Checking Charcoal Canister For Cracks Or Damage

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check charcoal canister operation.
   1. While holding the purge port closed, blow air at 1.67 kPa (17.0 gf/cm² , 0.24 psi) into the vent port, and check that the air flows from the air inlet port.

      If the result is not as specified, replace the charcoal canister assy.

      Fig 5: Checking Air Flows From Air Inlet Port

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. While holding the vent port closed, apply a vacuum of 1.10 kPa (8.3 mmHg, 0.32 in.Hg) into the purge port, and check that the air flows from the air inlet port.

      If the result is not as specified, replace the charcoal canister assy.

      Fig 6: Checking Air Flows From Air Inlet Port

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Check the air leakage.
   1. Remove the air hose between ports A and B.
   2. Connect the pressure gauge to the vent port of the charcoal canister.

      SST 09992-00242

   3. While holding port B, the purge port and the air inlet port closed and port A open, apply pressurized air at 19.6 kPa (0.2 kgf/cm² , 2.81 psi) into the vent port, then confirm that the pressure is retained.

      If the result is not as specified, replace the charcoal canister assy.

      Fig 7: Checking Air Leakage

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Check leak detection pump.
   1. Check that air flows from port A to ports B and C. If the result is not as specified, replace the pump module.
      Fig 8: Checking Air Flows From Port A To Ports B And C

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Apply battery positive voltage across the terminals.
   3. Check that the valve is closed.

      If the result is not as specified, replace the pump module.

      Fig 9: Checking Valve Is Closed

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

      Standard: 

      TESTER CONNECTION AND SPECIFIED CONDITION (1 OF 4)
      
      

      Tester Connection	Specified Condition
      1-2	26 to 300 at 20°C(68°F)

      Fig 10: Measuring Resistance Between Terminals

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   If the resistance is not as specified, replace the vacuum switching valve No. 1.

2. Check the vacuum switching valve No. 1 for ground.
   1. Using an ohmmeter, check the resistance between each terminal and the body.

      Standard: 

      TESTER CONNECTION AND SPECIFIED CONDITION (2 OF 4)
      
      

      Tester Connection	Specified Condition
      1 - Body	10 M Ω or higher
      2-Body	10MΩ or higher

      Fig 11: Checking Resistance Between Each Terminal And Body

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   If the resistance is not as specified, replace the vacuum switching valve No. 1.

3. Check the operation.
   1. Check that air does not flow from port E to F. If the operation is not as specified, replace the vacuum switching valve No. 1.
      Fig 12: Checking Air Does Not Flow From Port E To F

      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 the operation is not as specified, replace the vacuum switching valve No. 1.

      Fig 13: Checking Air Flows From Port E To Port F

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Check the resistance. (Bank 1 Sensor 1)
   1. Using an ohmmeter, measure the resistance between the terminals.

      Standard: 

      TESTER CONNECTION AND SPECIFIED CONDITION (3 OF 4)
      
      

      Tester Connection	Specified Condition
      1(HT)-2(+B)	1.8 to 3.4 Ω at 20°C (68°F)
      1(HT)-4(E1)	10 kΩ or higher

      Fig 14: Measuring Resistance Between Terminals

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If the result is not as specified, replace the air fuel ratio sensor.

1. Check the resistance. (Bank 1 Sensor 2)
   1. Using an ohmmeter, measure the resistance between the terminals.
      Fig 15: Measuring Resistance Between Terminals

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      TESTER CONNECTION AND SPECIFIED CONDITION (4 OF 4)
      
      

      Tester Connection	Specified Condition
      1(+B)-2(HT)	11 to 16 Ω at 20°C (68°F)
      2(HT)-3(E)	10 kΩ or higher

If the result is not as specified, replace the heated oxygen sensor.