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

DTC detecting condition: 

Detected when two consecutive driving cycles with fault occur.

After servicing or replacing faulty parts, perform Clear Memory Mode Ref. to ENGINE (DIAGNOSTICS) (H6DO)>CLEAR MEMORY MODE>OPERATION ., and inspection mode Ref. to ENGINE (DIAGNOSTICS) (H6DO)>INSPECTION MODE>PROCEDURE .

  1. CHECK DRAIN TUBE BETWEEN CANISTER AND LEAK CHECK VALVE ASSEMBLY  .

    Check the drain tube.

    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) (H6DO)>CANISTER .

    No: Go to  2 .

  2. CHECK HOSE AND TUBE BETWEEN CANISTER AND FUEL TANK  .

    Check the hose or 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) (H6DO)>CANISTER . Ref. to FUEL INJECTION (FUEL SYSTEMS) (H6DO)>FUEL TANK .

    No: Replace the canister. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H6DO)>CANISTER . After the operation is complete, go to the next step. Go to  3 .

  3. CHECK EVAPORATIVE EMISSION CONTROL SYSTEM  .

    Perform drive cycle I. Ref. to ENGINE (DIAGNOSTICS) (H6DO)>DRIVE CYCLE>PROCEDURE>DRIVE CYCLE I .

    Is DTC P1451 displayed on the display? (Current malfunction)

    Yes: Replace the leak check valve assembly. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H6DO)>LEAK CHECK VALVE ASSEMBLY .

    No: End.