DTC P0455, P0456: Notes
DTC P0455 : Evaporative Emission (EVAP) System Large Leak Detected
DTC P0456 : Evaporative Emission (EVAP) System Very Small Leak Detected
Special Tools Required
Vacuum Pump/Gauge, 0-30 inHg Snap-on YA4000A or equivalent, commercially available
Vacuum/Pressure Gauge, 0-4 inHg 07JAZ-001000B
How To Use This Service Information .
The fuel system is designed to allow specified maximum vacuum and pressure conditions. Do not deviate from the vacuum and pressure tests as indicated in these procedures. Excessive pressure/vacuum would damage the EVAP components or cause eventual fuel tank failure.
NOTE:
- Before you troubleshoot, review the How to Troubleshoot .
- Fresh fuel has a higher volatility that will create greater pressure/vacuum. The best condition for testing is less than a full tank of fresh fuel. If possible, to assist in leak detection, add 1 gallon of fresh fuel to the tank (as long as it will not fill the tank), just before starting these procedures.