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Test Description

The number below refers to the step number on the diagnostic table.

  1. 6:  A normal operating FTP sensor should increase above 5 inches of H2O and stop between 6-7 inches of H2O.
DTC P0455

Step Action Values Yes No
Schematic Reference: Evaporative Emissions (EVAP) Hose Routing Diagram
Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) Connector End Views
1 Did you perform the Diagnostic System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle
2
  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 .
  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 valve or EVAP canister
Did you find and correct the condition?		 - Go to Step 16  Go to Step 3 
3
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 Emission System Tester (EEST) power supply clips to a known good 12-volt source. See Special Tools .
  3. Install the GE-41415-50 Fuel Tank Cap Adapter to the fuel fill pipe.
  4. Connect the J 41413-200  nitrogen/smoke supply hose to the GE-41415-50 . See Special Tools .
  5. Turn ON the ignition, with the engine OFF.
  6. Command the EVAP canister vent solenoid valve closed with a scan tool.
  7. Turn the nitrogen/smoke valve on the J 41413-200  control panel to SMOKE. See Special Tools .
  8. Introduce smoke into the EVAP system with the remote switch.
  9. Open the EVAP service port with the J 41413-VLV  EVAP Port Vent Fitting. See Special Tools .
  10. Remove the J 41413-VLV  once smoke is observed.
  11. Continue to introduce smoke into the EVAP system for an additional 60 seconds.
  12. Inspect the entire EVAP system for exiting smoke with the J 41413-SPT  High Intensity White Light.
  13. 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 16  Go to Step 4 
4
  1. Disconnect the GE-41415-50 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. See Special Tools .
  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  . See Special Tools .
  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 16  Go to Step 5 
5
  1. Stop introducing smoke with the remote switch.
  2. Install the GE-41415-50 to the fuel fill pipe.
  3. Connect the J 41413-200  nitrogen/smoke supply hose and vehicle fuel fill cap to the GE-41415-50 . See Special Tools .
  4. Command the EVAP canister vent solenoid valve open with a scan tool.
  5. Compare the fuel tank pressure sensor parameter with a scan tool to the J 41413-200  pressure/vacuum gage.
Is the difference between the 2 gages less than the specified value?		 1 in H2O Go to Step 6  Go to Step 13 
6 
  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. See Special Tools .
  3. Pressurize the EVAP system to the first specified value with the J 41413-200  .
  4. Observe the fuel tank pressure sensor parameter with a scan tool.
Is the fuel tank pressure sensor parameter more than the second specified value?		 10 in H2O
5 in H2O		 Go to Step 7  Go to Step 13 
7
  1. Stop introducing nitrogen into the EVAP system with the remote switch.
  2. Increase the EVAP canister purge solenoid valve to 100 percent.
  3. Observe the fuel tank pressure sensor parameter with a scan tool.
Is the fuel tank pressure sensor parameter less than the specified value?		 1 in H2O Go to Diagnostic Aids Go to Step 8 
8 Disconnect the EVAP purge pipe from the EVAP canister purge solenoid valve.
Is the fuel tank pressure sensor parameter less than the specified value within 90 seconds?		 1 in H2O Go to Step 14  Go to Step 9 
9 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 12  Go to Step 10 
10 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 15  Go to Step 11 
11 Repair the pinched or obstructed EVAP vapor pipe.
Did you complete the repair?		 - Go to Step 16  -
12 Repair the restriction in the EVAP purge pipe.
Did you complete the repair?		 - Go to Step 16  -
13 Replace the fuel tank pressure (FTP) sensor. Refer to Fuel Tank Pressure Sensor Replacement .
Did you complete the replacement?		 - Go to Step 16  -
14 Replace the EVAP canister purge solenoid valve.
Did you complete the replacement?		 - Go to Step 16  -
15 Replace the EVAP canister. Refer to Evaporative Emission (EVAP) Canister Replacement (Short Wheel Base) or Evaporative Emission (EVAP) Canister Replacement (Long Wheel Base) .
Did you complete the replacement?		 - Go to Step 16  -
16
IMPORTANT: DO NOT exceed the specified value in this step. Exceeding the specified value may produce incorrect test results.
  1. Connect the J 41413-200  to the fuel fill pipe. See Special Tools .
  2. Turn the nitrogen/smoke valve to NITROGEN.
  3. Seal the EVAP system using the EVAP Purge/Seal function with a scan tool.
  4. Pressurize the EVAP system to the specified value.
  5. Observe the J 41413-200  pressure/vacuum gage for 5
Does the J 41413-200  pressure/vacuum gage remain constant? See Special Tools .		 5 in H2O Go to Step 17  Go to Step 3 
17 Compare the fuel tank pressure sensor parameter with a scan tool to the J 41413-200  pressure/vacuum gage.
Is the difference between the 2 gages less than the specified value?		 1 in H2O Go to Step 18  Go to Step 5 
18
  1. Observe the J 41413-200  pressure/vacuum gage. See Special Tools .
  2. Increase the EVAP canister purge solenoid valve to 100 percent.
Does the pressure decrease?		 - Go to Step 19  Go to Step 8 
19 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?		 - Go to Diagnostic Trouble Code (DTC) List - Vehicle System OK
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