Fault-Code Library · EVAP
P0455: EVAP system gross leak detected
The fuel-vapor system has a large leak or cannot seal during its self-test.
Common symptoms
- •Engine warning light
- •Fuel smell
- •Loose cap message
- •Usually no drivability symptom
Likely causes
- •Loose or missing fuel cap
- •Large cracked EVAP hose
- •Vent valve stuck open
- •Damaged charcoal canister
First checks
- •Check fuel cap fit and seal
- •Smoke-test the EVAP system
- •Command vent and purge valves
Important
Large EVAP leaks are often simple, but the system should be smoke-tested rather than guessed.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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