Is it safe to drive with a P0457 code?

Severity is low. Address P0457 sooner rather than later — driving with an active check engine light can worsen the problem or void emissions warranties.

How much does it cost to fix P0457?

Repair costs for P0457 typically range from $0 to $50 in the US, depending on the underlying cause. The most common fix is: Loose or missing gas cap (literally just tighten until it clicks).

What are the symptoms of P0457?

Check engine light. "Check gas cap" message on some vehicles.

Check Engine Code

P0457

EVAP System Leak Detected (Fuel Cap Loose / Off)

Severity: low DIY difficulty: 1/5 Typical cost: $0–$50

Last updated April 30, 2026

What P0457 means

Some vehicles set this code specifically when the EVAP self-test fails in the pattern that suggests the gas cap is loose or off — basically the ECM telling you 'check the gas cap.'

Symptoms

Check engine light
"Check gas cap" message on some vehicles

Likely causes (most common first)

Loose or missing gas cap (literally just tighten until it clicks)
Failed gas cap seal (cheap replacement)
Damaged filler neck

Can I keep driving?

Low — mostly emissions/economy

Typical repair cost

DIY fixes can start near $0 (parts only). Shop repairs for P0457 typically run up to $50 depending on the underlying cause and vehicle. Start with the most common cause — Loose or missing gas cap (literally just tighten until it clicks) — before throwing parts at it.