DTC P0456: Evaporative Emission System Leak Detected (Very Small Leak)

WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, 2011 Ford Fusion, 2010 Mercury Milan, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

P0456 - EVAPORATIVE EMISSION SYSTEM LEAK DETECTED (VERY SMALL LEAK)

Description:	The powertrain control module (PCM) monitors the complete evaporative emission (EVAP) control system for the presence of a very small fuel vapor leak. The system failure occurs when a fuel vapor leak from an opening as small as 0.508 mm (0.020 inch) is detected by the EVAP running loss monitor test.
Possible Causes:	Very small holes or cuts in the fuel vapor hoses/tubes Incorrect fuel vapor hose or tube connections to the EVAP system components EVAP system component seals leaking
Diagnostic Aids:	Verify the capless fuel tank filler pipe is sealed correctly. Install and remove the supplemental fueling adapter five times in the capless fuel tank filler pipe to clear debris on the seal. Refer to the Owner's Literature for the location of the supplemental fueling adapter in the vehicle. Check for incorrect connections or damaged vapor hoses. Visually inspect the EVAP canister inlet port, CV solenoid filter, and canister vent hose assembly for contamination or debris.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	GO to PINPOINT TEST HX .