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

WARNING: This page is about a different variant/trim than selected.

Fuel odor
There is a hole of more than 0.5 mm (0.020 in) dia. in evaporation system or fuel tank.

CAUTION: After servicing or replacing faulty parts, perform Clear Memory Mode Ref. to OPERATION , Clear Memory Mode, and Inspection Mode Ref. to PROCEDURE , Inspection Mode.

DIAGNOSTIC PROCEDURE

Step	Check	Yes	No
1 CHECK FUEL FILLER CAP. Turn the ignition switch to OFF. Check the fuel filler cap. NOTE: The DTC is stored in memory if fuel filler cap is or was loose or if the cap chain has caught while tightening.	Is the fuel filler cap tightened securely?	Go to step 2.	Tighten fuel filler cap securely.
2 CHECK FUEL FILLER CAP.	Is the fuel filler cap genuine?	Go to step 3.	Replace with a genuine fuel filler cap.
3 CHECK FUEL FILLER PIPE GASKET.	Is there any damage to the seal between fuel filler cap and fuel filler pipe?	Repair or replace the fuel filler cap and fuel filler pipe. Ref. to FUEL FILLER PIPE .	Go to step 4.
4 CHECK DRAIN VALVE. Install the delivery (test) mode fuse. Turn the ignition switch to ON. Operate the drain valve using the Subaru Select Monitor. NOTE: Drain valve can be operated using the Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .	Does the drain valve operate?	Go to step 5.	Replace the drain valve. Ref. to DRAIN VALVE .
5 CHECK PURGE CONTROL SOLENOID VALVE. Operate the purge control solenoid valve using the Subaru Select Monitor. NOTE: Purge control solenoid valve operation can be executed using Subaru Select Monitor. For detailed procedures, refer to "SYSTEM OPERATION CHECK MODE". Ref. to SYSTEM OPERATION CHECK MODE .	Does the purge control solenoid valve operate?	Go to step 6.	Replace the purge control solenoid valve. Ref. to PURGE CONTROL SOLENOID VALVE .
6 CHECK EVAPORATIVE EMISSION CONTROL SYSTEM LINE. Turn the ignition switch to OFF. Remove the delivery (test) mode fuse.	Is there any hole of more than 0.5 mm (0.020 in) dia. on evaporation line?	Repair or replace the evaporation line. Ref. to FUEL DELIVERY AND EVAPORATION LINES .	Go to step 7.
7 CHECK CANISTER.	Is the canister damaged or is there a hole of more than 0.5 mm (0.020 in) dia. in it?	Repair or replace the canister. Ref. to CANISTER .	Go to step 8.
8 CHECK FUEL TANK. Remove the fuel tank. Ref. to FUEL TANK .	Is the fuel tank damaged or is there any hole of more than 0.5 mm (0.020 in) dia. in it?	Repair or replace the fuel tank. Ref. to FUEL TANK .	Go to step 9.
9 CHECK ANY OTHER MECHANICAL TROUBLE IN EVAPORATIVE EMISSION CONTROL SYSTEM.	Is there any hole of more than 0.5 mm (0.020 in) dia, crack, clogging, or disconnections, bend, misconnection of hoses or pipes in evaporative emission control system?	Repair or replace the hoses or pipes.	Repair the poor contact of ECM connector.