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

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

CAUTION: After servicing or replacing faulty parts, perform Clear Memory Mode Ref. to ENGINE (DIAGNOSTICS) (STI)>Clear Memory Mode>OPERATION , and inspection mode Ref. to ENGINE (DIAGNOSTICS) (STI)>Inspection Mode>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) (STI)>Leak Check Valve Assembly .

No: GO to 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) (STI)>Canister . Ref. to FUEL INJECTION (FUEL SYSTEMS) (STI)>Fuel Tank .

NO: Replace the canister. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (STI)>Canister .

After the operation is complete, go to the next step. GO to 3.
CHECK EVAPORATIVE EMISSION CONTROL SYSTEM .
Perform drive cycle I. Ref. to ENGINE (DIAGNOSTICS) (STI)>Drive Cycle>PROCEDURE>DRIVE CYCLE I .

Is DTC P1451 displayed on the display?

Yes: Replace the leak check valve assembly. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (STI)>Leak Check Valve Assembly .

No: End.