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Test Description

WARNING: This page is about a different car, the 2004 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

  1. 2:  This step verifies that a failure condition is active.
  2. 4:  Introducing smoke in 15 second intervals may allow smaller leak areas to be more noticeable. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.
  3. 6:  This step verifies proper operation of the fuel tank pressure (FTP) sensor.
  4. 7:  A normal operating FTP sensor should increase above 5 inches of H20 and stop between 6 inches of H20 and 7 inches of H20.
  5. 9:  This step tests the EVAP canister purge solenoid valve vacuum source between the EVAP canister purge solenoid valve and the intake manifold for restrictions or blockages.
DTC P0455

Step Action Values Yes No
Schematic Reference:  Evaporative Emissions (EVAP) Hose Routing Diagram 
1 Did you perform the Diagnostic System Check-Engine Controls? - Go to Step 2  Go to Diagnostic System Check - Engine Controls
  1. Inspect the evaporative emission (EVAP) system for the following conditions:
    • Loose, missing, or damaged service port Schrader valve
    • Loose, incorrect, missing, or damaged fuel fill cap
    • A damaged EVAP canister purge solenoid valve
  2. Raise the vehicle on a hoist. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Inspect the EVAP system for the following conditions:
    • Disconnected, improperly routed, kinked, or damaged EVAP pipes and hoses
    • A damaged EVAP canister vent solenoid or EVAP canister
Did you find and correct the condition?
- Go to Step 23  Go to Step 3 
3
IMPORTANT: Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilize.
  1. Turn OFF the ignition.
  2. Connect the J 41413-200  Evaporative Emissions System Tester (EEST) power supply clips to a known good 12-volt source.
  3. Turn the nitrogen/smoke valve to nitrogen.
  4. Connect the nitrogen/smoke hose to the 0.5 mm (0.20 in) test orifice on the bottom-front of the J 41413-200  .
  5. Use the remote switch to activate the J 41413-200  .
  6. Align the red flag on the flow meter with the floating indicator. Use the remote switch to de-activate the J 41413-200  .
  7. Install the J 41415-40  to the fuel fill pipe.
  8. Install the fuel fill cap to the J 41415-40  .
  9. Remove the nitrogen/smoke hose from the test orifice and install the hose onto the J 41415-40  .
  10. Turn ON the ignition, with the engine OFF.
  11. Command the EVAP canister vent solenoid valve closed with a scan tool.
  12. Use the remote switch to introduce nitrogen and fill the EVAP system until the floating indicator stabilizes.
  13. Compare the flow meter's stable floating indicator position to the red flag.
Is the floating indicator below the red flag?
- Go to Step 6  Go to Step 4 
IMPORTANT: Ensure that the vehicle underbody temperature is similar to the ambient temperature and allow the surrounding air to stabilize before starting the diagnostic procedure. System flow will be less with higher temperatures.
  1. Turn OFF the ignition.
  2. Connect the J 41413-200  Evaporative Emissions System Tester (EEST) power supply clips to a known good 12-volt source.
  3. Install the J 41415-40  Fuel Tank Cap Adapter to the fuel fill pipe.
  4. Connect the fuel fill cap to the J 41415-40  .
  5. Connect the J 41413-200  nitrogen/smoke supply hose to the J 41415-40  .
  6. Turn ON the ignition with the engine OFF.
  7. Command the EVAP canister vent solenoid valve closed with a scan tool.
  8. Turn the nitrogen/smoke valve on the J 41413-200  control panel to SMOKE.
  9. Introduce smoke into the EVAP system with the remote switch.
  10. Open the EVAP service port with the J 41413-VLV  EVAP Service Port Vent Fitting.
  11. Remove the J 41413-VLV  once smoke is observed.
  12. Continue to introduce smoke into the EVAP system for an additional 60 seconds.
  13. Inspect the entire EVAP system for exiting smoke with the J 41413-SPT  High Intensity White Light.
  14. Continue to introduce smoke at 15 second intervals until the leak source has been located.
Did you locate and repair a leak source?
- Go to Step 23  Go to Step 5 
5
  1. Disconnect the J 41415-40  from the fuel fill pipe.
  2. Install the fuel fill cap to the fuel fill pipe.
  3. Connect the J 41413-200  nitrogen/smoke supply hose to the EVAP service port.
  4. Introduce smoke into the EVAP system with the remote switch.
  5. Inspect the entire EVAP system for exiting smoke with the J 41413-SPT  .
  6. Continue to introduce smoke at 15 second intervals until the leak source has been located.
Did you locate and repair a leak source?
- Go to Step 23  Go to Step 6 
  1. Stop introducing smoke with the remote switch.
  2. Install the J 41415-40  to the fuel fill pipe.
  3. Connect the J 41413-200  nitrogen/smoke supply hose to the J 41415-40  .
  4. Connect the vehicle fuel fill cap to the J 41415-40  .
  5. Command the EVAP canister vent solenoid valve open with a scan tool.
  6. Compare the Fuel Tank Pressure Sensor parameter with a scan tool to the J 41413-200  pressure/vacuum gage.
Is the difference between the two gages less than the specified value?
1 in H2O Go to Step 7  Go to Step 15 
  1. Seal the EVAP system using the EVAP Purge/Seal function with a scan tool.
  2. Turn the nitrogen/smoke valve on the J 41413-200  control panel to NITROGEN.
  3. Use the J 41413-200  to pressurize the EVAP system to the first specified value.
Is the Fuel Tank Pressure Sensor parameter more than the second specified value?
10 in H2O
5 in H2O
Go to Step 8  Go to Step 15 
8
  1. Stop introducing nitrogen into the EVAP system with the remote switch.
  2. Increase the EVAP canister purge solenoid valve to 100 percent.
Is the Fuel Tank Pressure sensor parameter less than the specified value?
1 in H2O Go to Step 9  Go to Step 11 
  1. Connect the nitrogen/smoke hose to the EVAP service port.
  2. Remove the J 41415-40  .
  3. Install the fuel fill cap to the fuel fill pipe.
  4. Start the engine.
  5. Allow the engine to idle.
  6. Use the purge/seal function to seal the system, with a scan tool.
  7. Command the EVAP canister purge solenoid valve to 30 percent.
  8. Observe the vacuum/pressure gage on the J 41413-200  and the FTP parameter on the scan tool.
  9. Allow the vacuum to increase on the gage of the J 41413-200  until it reaches approximately 16 in H2O.
  10. Use the purge/seal function to seal the system with a scan tool.
Is the FTP parameter on a scan tool within the specified value of the vacuum/pressure gage on the J 41413-200  until the vacuum reached the abort limit on a scan tool?
1 in H2O Go to Step 10  Go to Step 15 
10 Did the FTP parameter on a scan tool display more than the specified value? 3.2 V Go to Diagnostic Aids Go to Step 20 
11 Disconnect the EVAP purge vacuum source from the EVAP canister purge solenoid valve.
Is the Fuel Tank Pressure sensor parameter less than the specified value?
1 in H2O Go to Step 17  Go to Step 12 
12 Disconnect the EVAP purge pipe from the EVAP canister purge solenoid valve.
Is the Fuel Tank Pressure sensor parameter less than the specified value?
1 in H2O Go to Step 17  Go to Step 13 
13 Disconnect the EVAP purge pipe at the EVAP canister.
Is the Fuel Tank Pressure sensor parameter less than the specified value?
1 in H2O Go to Step 19  Go to Step 14 
14 Disconnect the EVAP vapor pipe at the EVAP canister.
Is the Fuel Tank Pressure sensor parameter less than the specified value?
1 in H2O Go to Step 22  Go to Step 18 
15 Test for an intermittent and for a poor connection at the fuel tank pressure (FTP) sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
- Go to Step 23  Go to Step 16 
16 Test the low reference circuit of the FTP sensor for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
- Go to Step 23  Go to Step 20 
17 Repair the pinched or obstructed EVAP purge solenoid valve vacuum source.
Did you complete the repair?
- Go to Step 23  -
18 Repair the pinched or obstructed EVAP vapor pipe.
Did you complete the repair?
- Go to Step 23  -
19 Repair the restriction in the EVAP purge pipe.
Did you complete the repair?
- Go to Step 23  -
20 Replace the FTP sensor. Refer to Fuel Tank Pressure Sensor Replacement .
Did you complete the replacement?
- Go to Step 23  -
21 Replace the EVAP canister purge solenoid valve. Refer to Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement (L36) or Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement (L67) .
Did you complete the replacement?
- Go to Step 23  -
22 Replace the EVAP canister. Refer to Evaporative Emission (EVAP) Canister Replacement .
Did you complete the replacement?
- Go to Step 23  -
23 Perform the Service Bay Test. Refer to Service Bay Test .
Does the scan tool indicate that the Service Bay Test passed?
- Go to Step 24  Go to Step 3 
24 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?
- Go to Diagnostic Trouble Code (DTC) List System OK