P0456Low urgency

EVAP System Small Leak Detected

Emission · EVAP System

Safe to drive — check gas cap first.
What this means

A very small EVAP system leak. Often caused by a loose or worn gas cap. If cap is fine, an EVAP smoke test will locate the leak.

Likely causes
  • Faulty gas capMost common
  • Small crack in EVAP hoseCommon
  • Loose fuel filler neckLess common
Estimated repair cost
Gas cap replacement$10 – $30
EVAP smoke test + repair$100 – $300
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Frequently asked questions

What does P0456 mean?

A very small EVAP system leak. Often caused by a loose or worn gas cap. If cap is fine, an EVAP smoke test will locate the leak.

Is P0456 serious?

Safe to drive — check gas cap first.

How much does it cost to fix P0456?

Repair costs for P0456 range from $10 – $30 depending on the root cause and your vehicle.

Can I drive with P0456?

Yes, the vehicle is safe to drive. Schedule a repair at your convenience.