EmissionsSeverity Low: usually safe to drive

P0457Evaporative Emission System Leak Detected (Fuel Cap Loose/Off)

What it means

After refuelling the ECU sees a large leak and assumes the fuel cap is loose or missing.

Symptoms

Check engine light
Possibly a fuel smell
Usually no change in how the car drives

Common causes

Fuel cap loose, missing or damaged
Filler neck seal damaged

What to check first

Tighten or replace the fuel cap
Inspect the filler neck sealing surface
Clear the code and drive; it should not return

Can I drive with P0457? Usually yes. P0457 rarely affects how the car drives, but it keeps the check engine light on and can fail an emissions test.

Generic OBD-II meaning. Manufacturer-specific meanings and checks can differ; always check the service information for the car.

Cases with P0457 (0)

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P0457: questions and answers

What does P0457 mean?

P0457: Evaporative Emission System Leak Detected (Fuel Cap Loose/Off). After refuelling the ECU sees a large leak and assumes the fuel cap is loose or missing.

What are the symptoms of P0457?

Check engine light. Possibly a fuel smell. Usually no change in how the car drives.

What causes P0457?

Fuel cap loose, missing or damaged. Filler neck seal damaged.

How do you diagnose P0457?

1. Tighten or replace the fuel cap 2. Inspect the filler neck sealing surface 3. Clear the code and drive; it should not return

Can I drive with P0457?

Usually yes. P0457 rarely affects how the car drives, but it keeps the check engine light on and can fail an emissions test.