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DTC/P0455

P0455: Evaporative Emission System Leak Detected (Large Leak)

Quick Answer
Moderata GravitàSicuro da guidare (a breve termine)Sistema EVAP

P0455 means the engine control unit has detected a large leak in the evaporative emission system. This is a more significant leak than P0442, often caused by a missing fuel cap, a completely disconnected EVAP hose, or a cracked charcoal canister. The large leak size usually makes it easier to find.

Costo di riparazione stimatoDa €10 a €480+, varia in base al veicolo

Cosa significa P0455?

P0455 means the engine control unit has detected a large leak in the evaporative emission system. This is a more significant leak than P0442, often caused by a missing fuel cap, a completely disconnected EVAP hose, or a cracked charcoal canister. The large leak size usually makes it easier to find.

P0455 è un codice diagnostico di guasto relativo a sistema evap, classificato con gravità moderate. Quando la centralina (ECU) del tuo veicolo rileva questa condizione, memorizza P0455 e accende la spia motore.

Quali sono i sintomi di P0455?

Se il tuo veicolo ha attivato P0455, potresti notare uno o più di questi sintomi:

  • Check engine light on
  • Noticeable fuel odour, especially in warm weather or after parking
  • Failed emissions test
  • Fuel cap warning indicator on some vehicles
  • No significant driveability issues

Cosa causa P0455?

Ecco le cause più comuni di P0455, ordinate in base alla probabilità che siano la causa del problema:

altaMissing or improperly seated fuel cap
altaDisconnected or split EVAP hose
mediaCracked charcoal canister
mediaFailed purge or vent valve (stuck open)
bassaDamaged fuel tank or filler neck

È sicuro guidare con P0455?

In genere sì, per brevi tragitti. A large EVAP leak does not affect driveability, but it means significant fuel vapour is escaping. Check the fuel cap immediately. Repair before your next emissions inspection.

Come si diagnostica P0455?

Segui questi passaggi per individuare la causa principale di P0455:

  1. Check the fuel cap immediately. If it is missing, loose, or the seal is visibly cracked, replace it, clear the code, and monitor over several drive cycles
  2. With the fuel cap confirmed good, perform a visual inspection of all EVAP hoses. Follow the lines from the fuel tank to the charcoal canister and from the canister to the engine. A large leak is often visible as a completely disconnected or split hose
  3. Perform a smoke test on the EVAP system. A large leak will produce a visible plume of smoke, making the source easy to locate
  4. Inspect the charcoal canister for cracks, particularly on the plastic housing and at the hose connection points
  5. If no external leak is found, test the purge valve and vent valve by commanding them with a scan tool. A vent valve stuck open during the EVAP test will register as a large leak

Quanto costa riparare P0455?

I costi di riparazione di P0455 variano a seconda della causa principale e del tuo veicolo. Ecco le stime tipiche:

Riparazione Costo dei ricambi Costo della manodopera Stima totale Difficoltà fai-da-te
Replace or re-seat fuel cap €10–€40 €0–€0 €10–€40 Facile
Replace disconnected or split EVAP hose €10–€50 €30–€120 €40–€170 Facile
Replace charcoal canister €60–€280 €60–€200 €120–€480 Moderata
Replace vent valve or purge valve €20–€100 €30–€120 €50–€220 Moderata

Prezzi stimati al March 2026. I costi variano in base alla regione, al veicolo e all'officina.

P0455 su veicoli specifici

P0455 si comporta in modo diverso a seconda del tuo veicolo. Seleziona la tua auto qui sotto per cause specifiche del modello, problemi noti e stime dei costi adeguate:

Opel

P0455 su Opel Corsa

2006-2024

The Corsa D and E have the charcoal canister mounted near the rear axle where it is exposed to road debris. Cracks in the canister housing are a known cause of P0455. The fuel cap uses a simple screw design that can lose its seal after frequent use.

Cosa causa P0455 su una Opel Corsa?

Opel CorsaCracked charcoal canister from road debris impact
Opel CorsaWorn fuel cap seal

Costo di riparazione di P0455 per Opel Corsa

Costi stimati per i proprietari di Opel Corsaadeguato al ribasso rispetto alla media a causa dei prezzi dei ricambi specifici Opel

Riparazione Costo dei ricambi Costo della manodopera Stima totale Difficoltà fai-da-te
Replace or re-seat fuel cap €9–€36 €0–€0 €9–€36 Facile
Replace disconnected or split EVAP hose €9–€45 €27–€108 €36–€153 Facile
Replace charcoal canister €54–€252 €54–€180 €108–€432 Moderata
Replace vent valve or purge valve €18–€90 €27–€108 €45–€198 Moderata

Prezzi stimati al March 2026. I costi variano in base alla regione, al veicolo e all'officina.

Ford

P0455 su Ford Fiesta

2008-2023

The Fiesta Mk7 has EVAP hoses routed along the underfloor near the fuel tank that can be damaged during service or by road debris. The purge valve on the 1.0 EcoBoost is mounted on top of the engine and is easy to test and replace.

Cosa causa P0455 su una Ford Fiesta?

Ford FiestaEVAP hose damage from underfloor routing
Ford FiestaPurge valve failure on 1.0 EcoBoost

Costo di riparazione di P0455 per Ford Fiesta

Costi stimati per i proprietari di Ford Fiestaadeguato al ribasso rispetto alla media a causa dei prezzi dei ricambi specifici Ford

Riparazione Costo dei ricambi Costo della manodopera Stima totale Difficoltà fai-da-te
Replace or re-seat fuel cap €9–€36 €0–€0 €9–€36 Facile
Replace disconnected or split EVAP hose €9–€45 €27–€108 €36–€153 Facile
Replace charcoal canister €54–€252 €54–€180 €108–€432 Moderata
Replace vent valve or purge valve €18–€90 €27–€108 €45–€198 Moderata

Prezzi stimati al March 2026. I costi variano in base alla regione, al veicolo e all'officina.

Volkswagen

P0455 su Volkswagen Polo

2005-2024

The Polo shares many EVAP components with the VW Golf. The N80 purge valve is a common failure point. On the 1.2 TSI and 1.4 TSI, the EVAP lines near the fuel tank can become brittle in cold climates, leading to cracks that produce large leaks.

Cosa causa P0455 su una Volkswagen Polo?

Volkswagen PoloN80 purge valve failure
Volkswagen PoloBrittle EVAP hoses near the fuel tank on TSI models
Skoda

P0455 su Skoda Fabia

2007-2024

The Fabia uses VW Group EVAP system components. The charcoal canister is located near the rear wheel arch and can suffer damage from road salt and debris. A loose fuel cap after refuelling is statistically the most common cause of P0455 on this model.

Cosa causa P0455 su una Skoda Fabia?

Skoda FabiaCharcoal canister damage from road salt and debris
Skoda FabiaLoose fuel cap after refuelling

Costo di riparazione di P0455 per Skoda Fabia

Costi stimati per i proprietari di Skoda Fabiaadeguato al ribasso rispetto alla media a causa dei prezzi dei ricambi specifici Skoda

Riparazione Costo dei ricambi Costo della manodopera Stima totale Difficoltà fai-da-te
Replace or re-seat fuel cap €10–€38 €0–€0 €10–€38 Facile
Replace disconnected or split EVAP hose €10–€48 €29–€114 €38–€162 Facile
Replace charcoal canister €57–€266 €57–€190 €114–€456 Moderata
Replace vent valve or purge valve €19–€95 €29–€114 €48–€209 Moderata

Prezzi stimati al March 2026. I costi variano in base alla regione, al veicolo e all'officina.

Questi codici compaiono spesso insieme a P0455 o indicano problemi correlati:

P0440P0442P0446P0456

Domande frequenti su P0455

Is P0455 serious?

It is not mechanically harmful and will not damage your engine. However, a large EVAP leak means significant fuel vapour is escaping into the atmosphere. The check engine light will cause an automatic failure at any EU vehicle inspection.

Can I just tighten the fuel cap to fix P0455?

If the cap was loose or missing, yes. Tighten it until it clicks and clear the code. The ECU will re-test the system over the next few drive cycles. If the code returns, there is an additional leak beyond the cap.

What is the difference between a small and large EVAP leak?

The ECU categorises leaks by size. P0442 is a small leak (equivalent to a pinhole), while P0455 is a large leak (equivalent to a 1mm or larger opening). Large leaks are usually easier to find because they often involve a disconnected hose or missing cap.

Why did P0455 appear after a fuel fill-up?

The most likely reason is that the fuel cap was not tightened properly after refuelling. On some vehicles, overfilling the tank (topping off past the first click of the nozzle) can also saturate the charcoal canister, triggering EVAP codes.

How much does it cost to fix P0455?

If the cause is a fuel cap, the fix costs 10 to 40 EUR. A hose replacement runs 40 to 170 EUR. A charcoal canister replacement is 120 to 480 EUR. Start with the cheapest possibility first, as the fuel cap is the culprit in a large percentage of cases.

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