P0455-EVAP SYSTEM LARGE LEAK

For a complete wiring diagram Refer to Section 8W.


  • When Monitored:

    With the engine running, during a cold start test with the fuel level above 12%, ambient temperature between 4° C and 32° C (39° F and 89° F) and the fuel system in closed loop. The test runs when the small leak test is maturing.

  • Set Condition:

    The PCM activates the EVAP Purge Solenoid to pull the EVAP system into a vacuum to close the ESM switch. Once the ESM switch is closed, the PCM turns the EVAP Purge solenoid off to seal the EVAP system. If the ESM switch reopens before the calibrated amount of time, a large leak error is detected. Two Trip Fault. Three good trips to turn off the MIL.


Possible Causes
  
INTERMITTENT DTC
  
EVAP PURGE SOLENOID VACUUM SUPPLY
  
EVAP PURGE HOSE/TUBE OBSTRUCTION
  
EVAP SYSTEM LEAK
  
EVAPORATIVE SYSTEM MONITOR SWITCH
  

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).


1.DTC IS ACTIVE

NOTE: Allow the vehicle to cool to ambient temperature before continuing with this procedure.


NOTE: A loose gas cap may have caused this DTC to set. Make sure gas cap is tight and in good condition. Make sure the gas cap meets OEM specifications.







Is the status Active for this DTC?

Yes
  • Go to 2


No

2.EVAP SYSTEM INSPECTION












Were any problems found?

Yes


No
  • Go to 3

3.EVAP PURGE SOLENOID



NOTE: The solenoid should hold vacuum for a minimum of 15 seconds.




NOTE: The vacuum should drop when the solenoid is actuated.



Does the solenoid function as described above?

Yes
  • Go to 4


No

4.EVAP PURGE HOSE/TUBE OBSTRUCTION




Were any problems found?

Yes


No
  • Go to 5

5.CHECKING THE EVAPORATIVE SYSTEM FOR LEAKS



Were any problems found?

Yes


No
  • Go to 6

6.EVAPORATIVE SYSTEM MONITOR SWITCH






Were any problems found?

Yes


No