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DTC P1451: EVAP System Clog Detected (Pipe): Notes

1. -

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Refer to ENGINE (Diagnostics) (H4DOTC)>Basic Diagnostic Procedure>PROCEDURE .

CHECK DRAIN TUBE BETWEEN CANISTER AND LEAK CHECK VALVE ASSEMBLY .
Check the drain tube between the canister and leak check valve assembly.

Is the drain tube between canister and leak check valve assembly clogged?

Yes : Replace the drain tube between the canister and leak check valve assembly. Refer to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>CANISTER .

No : Go to 2.
CHECK HOSE AND TUBE BETWEEN CANISTER AND FUEL TANK .
Check the hose and tube between the canister and fuel tank.

Are the hose and tube between the canister and fuel tank clogged?

Yes : Replace the hose or tube between the canister and fuel tank. Refer to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>CANISTER . Refer to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL TANK .

No : Replace the canister. Refer to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>CANISTER . Go to 3.
CHECK EVAPORATIVE EMISSION CONTROL SYSTEM .
1. Perform the corresponding inspection mode. Refer to ENGINE (DIAGNOSTICS) (H4DOTC)>INSPECTION MODE .
2. Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Refer to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC) .
Is DTC P1451 displayed? (Current malfunction)

Yes : Replace the leak check valve assembly. Refer to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>LEAK CHECK VALVE ASSEMBLY .

No : End.