What does code P0456 mean and is it safe to drive?
P0456: Evaporative Emission System Leak Detected (Very Small Leak). Here’s what it means, what usually causes it, what repairs typically cost, and how urgent it is to keep driving.
Powertrain
What this code means
The EVAP system has detected a very small leak—often smaller than P0442. Commonly caused by a loose fuel cap or hairline crack in a hose.
Common causes
- Loose or worn gas cap seal
- Hairline crack in EVAP hoses
- Minor leak at purge or vent valve fittings
Symptoms
- Check Engine Light only
- Usually no noticeable driving symptoms
Typical fixes
- Inspect and replace gas cap if seal is hardened or cracked
- Smoke-test EVAP system to locate tiny leaks
- Repair or replace leaking hoses and fittings
Repair cost range
Repairs for P0456 often fall between $25 and $350, depending on the cause and your vehicle.