Code status
Needs verification
Not yet verified against SAE J2012_202509 / J2012DA. Treat unverified rows as a lookup aid, not repair authority.
- System
- Emissions
- Scope
- iso-sae-controlled-p0
- Standard
- SAE J2012 / ISO 15031-6
- Source
- legacy-import
Diagnostic boundary
A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.
Do not assume every P0457 is only the cap; a recurring leak after a known-good cap still needs EVAP-system testing.
Useful checks before replacing parts
- Inspect the fuel cap seal, cap installation, filler neck sealing surface, and cap tether or obstruction.
- Check EVAP hoses, purge valve, vent valve, and tank fittings if the code returns after correcting the cap.
- Use a smoke test or manufacturer leak test if visual cap and filler checks do not solve the leak.
Related OBD-II codes
These nearby emissions entries can help compare wording and fault area. They may share the same verification status as the source database.