P0457: EVAP Control System Leak Detected (Fuel Filler Cap Loose/Off)

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P0457 - EVAP CONTROL SYSTEM LEAK DETECTED (FUEL FILLER CAP LOOSE/OFF)

Description:	A fuel tank pressure change less than a minus (-) 7 inches of water in 30 seconds has occurred after refueling; or there is excessive purge (fuel vapor) flow greater than 0.06 pounds per minute
Possible Causes:	Fuel filler cap not installed on refueling (storing continuous memory DTC) and the fuel cap indicator lamp (FCIL) may also be illuminated. Damaged, missing or loosely installed fuel filler cap.
Diagnostic Aids:	Check for a missing fuel filler cap or the integrity of the cap. If OK, clear continuous memory DTCs and re-initiate the EVAP Emission Running Loss Monitor Drive Cycle.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	-	-	GO to PINPOINT TEST HX: EVAPORATIVE EMISSION (EVAP) MONITOR AND SYSTEM Step 50.