P0457 means the ECU detected an evaporative system leak consistent with a loose, missing, or damaged fuel cap. The code is specifically tuned to flag cap-sized leaks before flagging generic small (P0442) or large (P0455) leaks. The first thing to check is always the cap itself.
P0457 means the ECU detected an evaporative system leak consistent with a loose, missing, or damaged fuel cap. The code is specifically tuned to flag cap-sized leaks before flagging generic small (P0442) or large (P0455) leaks. The first thing to check is always the cap itself.
P0457 is a evap system-related diagnostic trouble code classified as low severity. When your vehicle's ECU detects this condition, it stores P0457 and illuminates the check engine light.
If your vehicle has triggered P0457, you may notice one or more of these symptoms:
Here are the most common causes of P0457, ranked by how likely they are to be the culprit:
Generally yes, for short-term driving. P0457 is specifically a fuel cap leak code and has no effect on engine performance or safety. Tighten the cap immediately and drive normally. The check engine light will cause an automatic fail at any EU emissions inspection until the code clears.
Follow these steps to pinpoint the root cause of P0457:
Repair costs for P0457 vary depending on the root cause and your vehicle. Here are typical estimates:
Prices estimated as of March 2026. Costs vary by region, vehicle, and shop.
P0457 behaves differently depending on your vehicle. Select your car below for model-specific causes, known issues, and adjusted cost estimates:
These codes are often seen alongside P0457 or indicate related issues:
After tightening the cap or replacing it, the ECU needs 3 to 5 complete drive cycles to retest the EVAP system and clear the code. A drive cycle includes a cold start, mixed driving over 15 to 20 minutes, and shutdown. You can also clear it manually with a scan tool to confirm the fix immediately.
Yes. P0457 is specifically tuned to the leak size associated with a loose or missing fuel cap (typically a medium-size leak). The ECU sets P0457 rather than the generic P0455 (large leak) or P0442 (small leak) when the leak profile matches a cap-sized opening, giving the driver a more specific hint.
If you've already tightened the cap and the light returns, the rubber seal is most likely worn, cracked, or contaminated with fuel residue. Replacement caps cost 10 to 40 EUR and take seconds to install. Always buy a manufacturer-spec or OEM-equivalent cap, not the cheapest universal option.
Yes, indirectly. Overfilling the tank past the first click of the fuel nozzle can saturate the charcoal canister with liquid fuel. A saturated canister cannot hold vacuum properly during EVAP self-tests and can set leak codes including P0457. The fix is to stop topping off and let the system self-recover over several drive cycles.
A petrol smell in your car can be a loose fuel cap or a dangerous fuel leak. Learn what each cause means and when the smell is a genuine fire risk.
Your check engine light just came on. Can you keep driving? It depends on whether the light is steady or flashing, and how the car actually feels.
Your car logged P0457. Skanyx reads it on any standard Bluetooth OBD2 adapter, tells you whether it is safe to keep driving, and breaks down the likely repair so you know the number before a shop quotes you.
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