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Test Description

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 purge solenoid valve vacuum source between the EVAP 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
2 
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Perform the Service Bay Test. Refer to Service Bay Test .
Does the scan tool indicate that the Service Bay Test passed?		 - Go to Diagnostic Aids Go to Step 3 
3
  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 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 vent solenoid valve or EVAP canister
Did you find and correct the condition?		 - Go to Step 19  Go to Step 4 
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 Fill 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 vent solenoid valve CLOSED with a scan tool.
  8. Turn the nitrogen/smoke valve on the J 41413-200  control panel to SMOKE.
  9. Use the remote switch to introduce smoke into the EVAP system.
  10. Use the J 41413-VLV  EVAP Service Port Vent Fitting to open the EVAP service port.
  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 19  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. Use the remote switch to introduce smoke into the EVAP system.
  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 19  Go to Step 6 
6 
  1. Use the remote switch to stop introducing smoke.
  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 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 scan tool Fuel Tank Pressure Sensor parameter within the specified value of the J 41413-200  pressure/vacuum gage?		 1 in H2O Go to Step 7  Go to Step 16 
7 
  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 16 
8
  1. Use the remote switch to stop introducing nitrogen into the EVAP system.
  2. Increase the EVAP purge solenoid valve to 100 percent.
Is the Fuel Tank Pressure sensor parameter less than the specified value?		 1 in H2O Go to Diagnostic Aids Go to Step 9 
9  Disconnect the EVAP purge vacuum source from the EVAP purge solenoid.
Is the Fuel Tank Pressure sensor parameter less than the specified value?		 1 in H2O Go to Step 13  Go to Step 10 
10 Disconnect the EVAP purge pipe from the EVAP purge solenoid.
Is the Fuel Tank Pressure sensor parameter less than the specified value?		 1 in H2O Go to Step 13  Go to Step 11 
11 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 15  Go to Step 12 
12 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 18  Go to Step 14 
13 Repair the pinched or obstructed EVAP purge solenoid valve vacuum source.
Did you complete the repair?		 - Go to Step 19  -
14 Repair the pinched or obstructed EVAP vapor pipe.
Did you complete the repair?		 - Go to Step 19  -
15 Repair the restriction in the EVAP purge pipe.
Did you complete the repair?		 - Go to Step 19  -
16 Replace the FTP sensor. Refer to Fuel Tank Pressure Sensor Replacement .
Did you complete the replacement?		 - Go to Step 19  -
17 Replace the EVAP purge solenoid valve. Refer to Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement .
Did you complete the replacement?		 - Go to Step 19  -
18 Replace the EVAP canister. Refer to Evaporative Emission (EVAP) Canister Replacement .
Did you complete the replacement?		 - Go to Step 19  -
19 Perform the Service Bay Test. Refer to Service Bay Test .
Does the scan tool indicate that the Service Bay Test passed?		 - Go to Step 20  Go to Step 3 
20 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
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