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ENRUDEPLES

P0455 — Evaporative Emission Control System Leak Detected (Gross Leak)

minor

What it means

The EVAP system could not build or hold any noticeable vacuum during the self-test, which points to a large opening — a missing fuel cap, a disconnected hose or a valve stuck wide open. This is the coarsest of the leak codes and it usually sets quickly, often on the drive right after refuelling. A strong petrol smell near the car is a typical accompanying sign.

Likely causes (most common first)

  1. Fuel filler cap missing, not screwed on or with a broken seal
  2. EVAP hose disconnected, split or eaten through by corrosion
  3. Purge valve stuck fully open
  4. Vent valve stuck open or its hose knocked off, common after underbody impacts
  5. Cracked charcoal canister or filler neck
  6. Leaking fuel pump flange seal or damaged plastic fuel tank

Can you drive with it?

Driving is allowed, but a strong fuel smell means a real vapour leak — check the cap and hoses now.

This is the generic meaning. What about your car?

The same code has different typical culprits on different engines. Tell the AI your make, model and year — it will rank the causes for your exact car and give you a check order.

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