P0457 FORD EVAP Control System Leak Detected Fuel Filler Cap Loose/Off

Possible causes
– Missing fuel filler cap
– Incorrect fuel filler cap used
– Fuel filler cap remains open or fails to close
– Foreign matter caught in fuel filler cap
Tech notes
It is a very common problem with Ford vehicles. There are service bulletins for the following vehciles:

1997-2000 Ford Contour
1997-2002 Ford Escort
1997-2003 Ford Crown Victoria
1997-2003 Ford Mustang
1997-2003 Ford Taurus
1998-2003 Ford Escort ZX2
2000-2003 Ford Focus
2002-2003 Ford Thunderbird
1997 Ford F-250 HD
1997-1999 Ford Ford F-250 LD
1997-2003 Ford E Series
1997-2003 Ford Expedition
1997-2003 Ford Explorer
1997-2003 Ford F-150
1997-2003 Ford Ranger
1997-2003 Ford Windstar
1999-2003 Ford F Super Duty
2000-2003 Ford EXCURSION
2001-2003 Ford ESCAPE
2001-2003 Ford Explorer
Ford Factory Service Bulletin OBDII Code P0457

When is the code detected?
EVAP control system has a very large leak such as fuel filler cap fell off, EVAP control system does not operate properly.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
– Possible a noticeable fuel odor caused by the release of fuel vapors
P0457 FORD Description
Vehicles that meet enhanced evaporative requirements utilize a vacuum-based evaporative system integrity check. The evap system integrity check uses a Fuel Tank Pressure Transducer (FTPT), a Canister Vent Solenoid (CVS) and Fuel Level Input (FLI) along with the Vapor Management Valve (VMV) or Electric Vapor Management Valve (EVMV) to find 0.040