P0455
EVAP System Leak Detected - Large Leak
Powertrain · Generic (all makes)System: Emissions
Safe to drive short term. Book a repair.
Likely causes
- Gas cap missing or loose
- Disconnected EVAP hose
- Vent valve stuck open
What to check first
A large EVAP leak is very often the gas cap left off or loose. Tighten or replace it and clear the code.
Typical repair cost
$30 – $450
Independent-shop parts and labor for the usual fix. Your price depends on the actual cause and the vehicle.
Next step
General information, not a diagnosis of your vehicle. Repair costs are typical shop ranges, not quotes.