Evaporative Emission System Leak Detected (Large Leak)
Common Symptoms
- Check engine light on
- Fuel smell near vehicle
- May fail emissions test
- No drivability symptoms typically
Most Likely Root Causes
- Loose or missing fuel cap
- Cracked or damaged EVAP hose
- Faulty purge valve (stuck open or closed)
- Failed vent valve
- Cracked charcoal canister
- Fuel tank leak
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Severity / Derate Risk
Low — no drivability impact. Emissions failure likely.
Component Location
Charcoal canister typically near fuel tank or in engine bay. Purge valve on intake manifold or vacuum line. Vent valve at canister.
Manufacturer Notes
Always check fuel cap first — it is the most common cause and free to fix. A loose cap can set P0455 within one drive cycle.
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