P0457: EVAP System Leak Detected (fuel cap loose/off)
A generic powertrain (engine and transmission) trouble code, same meaning on every brand.
Yes - and check the gas cap right now, it may be the whole story.
Symptoms
- Check engine light soon after refueling
- Fuel smell if a hose is loose
Likely causes, most common first
- Gas cap loose or missing (the classic)
- Cap seal cracked
- Filler neck or hose leak
Read P0457 yourself before paying for diagnosis
A basic Bluetooth OBD-II scanner ($20-40) plugs into the port under the dashboard and shows this code with live sensor data on your phone - useful both for confirming the fix and for talking to a shop from an informed position.
What is going on and how it gets diagnosed
P0457 is the leak-detected-with-evidence-of-refueling code: several manufacturers use it specifically when the leak appeared right after the tank was filled - which points a very long finger at the cap.
Tighten to the click or replace the cap, clear the light, and only investigate further if it returns.
Repair options and cost
Typical US independent-shop ranges, parts and labor. Dealers run higher; regional labor rates vary.
Owner reports mentioning P0457
“I have called ford many times, as I have the same problem all the time, it shows that my car has an evaporative emission system leak code p0457. This is the 4th time that shows the same problem even after 'fixing'. Ford escape had this recall in 2016 but for some reason I was not sent a notice.”2011 Ford Escape · Mar 2021
“Gas filler neck gross evap leak / canister purge valve leak/ codes p0455 p0457 I was told that ford makes mazda parts and ford escape suv trucks are known for these problems with evap system?? *tr”2011 Mazda Tribute · Jan 2020 · 92,000 mi
“Secondary pump needs to be replaced: the check engine light was on. The vehicle has under 55,000 miles and failed emissions test with the following codes: p0457, p0455, p0456. An evap system smoke test was performed and found a leaking secondary unit. Needs secondary pump replaced.”2006 Chrysler Pacifica · Jun 2019 · 54,000 mi
Show 4 more owner reports
“Engine light was on and intermittently smelled gas or got fuel fill check indicator. Upon diagnostic mil p0455 and p0457. Canister purge valve had to be replaced paid $300. Going through my records I found that on april 5,2016, I had a recall 15s34 fuel tank and canister purge valve inspection completed. There was no evidence of cracks or leaks so only recalibration was completed. Now less than 10,000 miles later a replacement was needed. Awaiting review for a refund from ford dealership”2010 Mercury Milan · Jul 2017 · 75,133 mi
“Code p0457 and p1450 keep coming up. The description is a fault with the fuel filler near the gas tank. A recall for the fuel gas tank filler was previously performed. Is this part of this recall?”2011 Ford Fusion · Mar 2017
“Two codes keep coming up. P0457 and p1450. These are for the emissions evaporation system. The dealer has completed recall repair and claims it is ok.”2011 Ford Fusion · Dec 2016 · 152,665 mi
“During initial acceleration the car will lose power and start shaking sporadically. The car will not stall but it does not accelerate even when the gas peddle is depressed. The car has to be restarted to stop behavior. Check engine light appeared after the behavior persisted for about a week. Brought car to an auto zone for an odbii reading. The codes that were reported are as follows: p2111: throttle actuator control system - stuck open. P0457: evap small leak detected brought car to ford dealer as problem persisted. Ford dealer diagnosed problem as electronic throttle body failure. Electronic throttle body was replaced. *tr”2010 Ford Fusion · Jun 2013 · 65,087 mi
Cars that report P0457 most often
Based on mentions of this code in NHTSA owner complaints.
Frequently asked questions
Can I drive with P0457?
Yes - and check the gas cap right now, it may be the whole story.
How much does it cost to fix P0457?
Typical US repair costs range from $10 for the simplest fix (gas cap) to $400 in the worst case. The right number depends on which cause your car has - see the causes list.
Definition per SAE J2012 standard nomenclature. Symptoms, causes and costs are editorial guidance - always confirm with a diagnosis of your specific vehicle.