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

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. Ref. 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. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>LEAK CHECK VALVE ASSEMBLY .

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. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>CANISTER . Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL TANK .

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

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

No : End.