Leak Check Procedure (Sub-Diagnostic Procedure)

HINT:

The EVAP Pressure Tester procedures for checking the LEAK CHECK are available (see LEAK CHECK PROCEDURE (SUB-DIAGNOSTIC PROCEDURE) ).

1. CHECK THAT FUEL TANK CAP IS CORRECTLY INSTALLED 
   1. Check that the fuel tank cap is installed.
   2. Check that the fuel tank cap meets OEM specifications.
   3. Check that the fuel tank cap and fuel tank cap gasket are not damaged.
   4. Check that the fuel tank cap is correctly installed.

   HINT:

   • When using EVAP TESTER GAS CAP ADAPTOR:

     Use the GAS CAP ADAPTOR to check if pressure is leaking as a result of the fuel tank cap. The procedures for using the gas cap adaptor are located in the LEAK CHECK section, step 1-(b) (see LEAK CHECK PROCEDURE (SUB-DIAGNOSTIC PROCEDURE) ).

   • If the fuel tank cap is not properly fastened, the EVAP system will be unable to maintain enough negative pressure (vacuum). The ECM may interpret the pressure leak as a system malfunction and set a DTC.
   1. OK : Go to step   3 
   2. NG : Go To Next Step. 
2. CORRECTLY INSTALL FUEL TANK CAP , AND RESTART ACTIVE TEST "LEV II SYS CHECK" (See  SYSTEM CHECK PROCEDURE BY OPERATION OF HAND-HELD TESTER  ) 
   1. Remove and reinstall the fuel tank cap. Tighten and twist the cap until a click sound is heard. If necessary, replace the fuel tank cap with an OEM specification cap.
   2. For each step in the ACTIVE TEST's LEV II SYS CHECK, the FTP sensor values should be within the given standard values.

   HINT:

   To confirm that the system's pressure leakage occurred as a result of the a loose or damaged cap, perform the EVAP system check (See DESCRIPTION OF EVAP SYSTEM CHECK  and SYSTEM CHECK PROCEDURE BY OPERATION OF HAND-HELD TESTER ).

   1. OK : SYSTEM IS NORMAL 
   2. NG : Go To Next Step. 
3. CHECK FILLER NECK DAMAGE 
   1. Remove the fuel tank cap.
   2. Visually inspect the filler neck for damage.
   3. Reinstall the fuel tank cap.
   Fig 1: Checking Filler Neck Damage

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG : REPLACE FUEL TANK INLET PIPE (FILLER NECK) 
   2. OK : Go To Next Step. 
4. ELIMINATE VSV FOR CCV AS SOURCE OF LEAKAGE (See  CCV CHECK PROCEDURE (SUB-DIAGNOSTIC PROCEDURE)  ) 

   HINT:

   Check that the CCV is not stuck open and does not have leakage.

   1. NG : REPAIR AFFECTED MALFUNCTION PART 
   2. OK : Go To Next Step. 
5. INSPECT HOSE AND TUBES (EVAP VSV - CHARCOAL CANISTER, FUEL TANK - CHARCOAL CANISTER) 
   1. Check that the vacuum hoses are connected correctly.
   2. Check that the vacuum hoses are not loose or disconnected.
   3. Check the vacuum hoses and tubes for cracks, holes, damage, or blockage.
   Fig 2: Inspecting Hose And Tubes (EVAP VSV - Charcoal Canister, Fuel Tank - Charcoal Canister)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG : REPAIR OR REPLACE DEFECTIVE OR DAMAGED HOSE OR TUBE 
   2. OK : Go To Next Step. 
6. CHECK FOR EVAPORATIVE EMISSIONS LEAK 
   1. Check if any hoses close to the fuel tank have been modified, and check if there are signs of any damage near the fuel tank or the charcoal canister.
      1. Check for cracks, deformation or loose connections of the following parts:
         • Fuel tank
         • Charcoal canister
         • Fuel tank filler pipe
         • Hoses and tubes around fuel tank and charcoal canister
      Fig 3: Checking For Evaporative Emissions Leak

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG : REPAIR OR REPLACE DEFECTIVE OR DAMAGED COMPONENTS 
   2. OK : Go To Next Step. 
7. INSPECT CHARCOAL CANISTER (See  EMISSION CONTROL (3MZ-FE)  ) 
   1. NG : REPLACE CHARCOAL CANISTER 
   2. OK : Go To Next Step. 
8. INSPECT FUEL TANK (See  FUEL (3MZ-FE)  ) 
   1. Check that the hose, tube and attached parts are connected correctly.
   2. Check the fuel tank for cracks, hole and damage.
   1. NG : REPAIR OR REPLACE DEFECTIVE OR DAMAGED PARTS 
   2. OK : SYSTEM IS OPERATING NORMALLY 

1. LEAK CHECK (WHEN USING EVAP CONTROL SYSTEM TEST EQUIPMENT VACUUM GAUGE) 

   HINT:

   The EVAP control system test equipment vacuum gauge is useful for finding leaks.

   1. Get the base-line reading of the system leak.

      HINT:

      First make a note of the change in pressure within the system. Then, use this note as a criteria for steps (b) to (c).

      1. Connect the pressure gauge (EVAP control system test equipment vacuum gauge) to the EVAP service port on the purge line.
         Fig 4: Connecting Pressure Gauge To EVAP Service Port On Purge Line

         Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. The ignition switch is ON but the engine is not running.
      3. Enter the following menus: DIAGNOSIS/ENHANCED OBD II/ACTIVE TEST/CAN CTRL VSV. Press the right arrow key.
      4. Close the CCV (CCV is ON).
      5. From the EVAP service port, apply 786 to 790 mmHg-a (24 to 28 mmHg-g) of pressure. Do not apply pressure continuously for more than 45 seconds.

         Once pressure is added, maintain the pressure and seal the system.

         Fig 5: Applying Pressure

         Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002