Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means your car thinks the gas cap is loose or missing. It's like when you forget to put the lid back on a jar, and things can spill out.
The P0457 code is triggered when the vehicle's computer detects a large leak in the EVAP system, often due to a loose or missing fuel cap.
The EVAP (Evaporative Emission Control System) prevents fuel vapors from escaping into the atmosphere. A P0457 code indicates a large leak in this system, typically caused by a loose or missing fuel cap, but it can also be due to other leaks in the system.
• Check Engine Light is on
• Slight smell of fuel
• Possible decrease in fuel efficiency
• Loose or missing fuel cap
• Damaged or cracked fuel cap
• Leak in the EVAP system hoses or connections
EVAP: Evaporative Emission Control System
OBD-II: On-Board Diagnostics, Second Generation
• Check if the fuel cap is properly tightened.
• Inspect the fuel cap for damage.
• Examine the EVAP system for leaks or damaged components.
• Tighten or replace the fuel cap.
• Repair or replace any damaged EVAP system components.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Fuel cap tester
• Smoke machine for leak detection
$20 - $150
Easy
• Ford F-150
• Honda Accord
• Toyota Camry
• Always ensure the fuel cap is tightened after refueling.
• Regularly inspect the fuel cap for damage.
• Have the EVAP system checked during routine maintenance.
Emission Control System
• Check the fuel cap first as it's the most common cause.
• If the problem persists, consult a professional mechanic.
Check with your vehicle manufacturer for warranty coverage on emission-related components.
The P0457 code has been a common issue since the introduction of OBD-II systems, often due to user error with the fuel cap.
Low – This code doesn't affect immediate drivability but should be addressed to prevent emissions issues.
Ignoring this code can lead to increased emissions, which may be illegal in some areas and could result in fines.
• Vehicle must be running
• Fuel level should be between 15% and 85%
The fuel cap is located on the fuel filler neck, usually on the side of the vehicle.
Q: Can I drive with a P0457 code?
A: Yes, but it's best to fix it soon to avoid emissions issues.
Q: Will a loose fuel cap cause my car to fail an emissions test?
A: Yes, a loose fuel cap can cause your car to fail an emissions test.
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Fitment Required · Vehicle-fitment part
Relevant for some EVAP leak codes where the fuel cap or sealing surface is part of the problem.
Some EVAP leak faults involve the fuel cap or its sealing surface.
Fuel caps vary by vehicle and should be matched to the exact application.
View options on Amazon
Fitment Required · Vehicle-fitment part
Relevant when EVAP diagnosis points toward purge-flow or purge-control faults.
EVAP diagnosis often includes purge-flow and valve-control faults.
Confirm the failed valve and exact fitment before buying parts.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.