P0455: Evaporative Emission System Leak Detected (Large Leak)
Moderate SeveritySafe to drive (short-term)EVAP System
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.
What does P0455 mean?
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 is a evap system-related diagnostic trouble code classified as moderate severity. When your vehicle's ECU detects this condition, it stores P0455 and illuminates the check engine light.
What are the symptoms of P0455?
If your vehicle has triggered P0455, you may notice one or more of these symptoms:
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
What causes P0455?
Here are the most common causes of P0455, ranked by how likely they are to be the culprit:
highMissing or improperly seated fuel cap
highDisconnected or split EVAP hose
mediumCracked charcoal canister
mediumFailed purge or vent valve (stuck open)
lowDamaged fuel tank or filler neck
Is it safe to drive with P0455?
Generally yes, for short-term driving. 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.
How do you diagnose P0455?
Follow these steps to pinpoint the root cause of P0455:
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
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
Perform a smoke test on the EVAP system. A large leak will produce a visible plume of smoke, making the source easy to locate
Inspect the charcoal canister for cracks, particularly on the plastic housing and at the hose connection points
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
How much does P0455 cost to fix?
Repair costs for P0455 vary depending on the root cause and your vehicle. Here are typical estimates:
Repair
Parts Cost
Labor Cost
Total Estimate
DIY Difficulty
Replace or re-seat fuel cap
€10–€40
€0–€0
€10–€40
Easy
Replace disconnected or split EVAP hose
€10–€50
€30–€120
€40–€170
Easy
Replace charcoal canister
€60–€280
€60–€200
€120–€480
Moderate
Replace vent valve or purge valve
€20–€100
€30–€120
€50–€220
Moderate
Prices estimated as of March 2026. Costs vary by region, vehicle, and shop.
P0455 on specific vehicles
P0455 behaves differently depending on your vehicle. Select your car below for model-specific causes, known issues, and adjusted cost estimates:
P0455 on Opel Corsa
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.
What causes P0455 on a Opel Corsa?
Opel CorsaCracked charcoal canister from road debris impact
Opel CorsaWorn fuel cap seal
P0455 repair cost for Opel Corsa
Estimated costs for Opel Corsa ownersadjusted lower than average due to Opel-specific parts pricing
Repair
Parts Cost
Labor Cost
Total Estimate
DIY Difficulty
Replace or re-seat fuel cap
€9–€36
€0–€0
€9–€36
Easy
Replace disconnected or split EVAP hose
€9–€45
€27–€108
€36–€153
Easy
Replace charcoal canister
€54–€252
€54–€180
€108–€432
Moderate
Replace vent valve or purge valve
€18–€90
€27–€108
€45–€198
Moderate
Prices estimated as of March 2026. Costs vary by region, vehicle, and shop.
P0455 on Ford Fiesta
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.
What causes P0455 on a Ford Fiesta?
Ford FiestaEVAP hose damage from underfloor routing
Ford FiestaPurge valve failure on 1.0 EcoBoost
P0455 repair cost for Ford Fiesta
Estimated costs for Ford Fiesta ownersadjusted lower than average due to Ford-specific parts pricing
Repair
Parts Cost
Labor Cost
Total Estimate
DIY Difficulty
Replace or re-seat fuel cap
€9–€36
€0–€0
€9–€36
Easy
Replace disconnected or split EVAP hose
€9–€45
€27–€108
€36–€153
Easy
Replace charcoal canister
€54–€252
€54–€180
€108–€432
Moderate
Replace vent valve or purge valve
€18–€90
€27–€108
€45–€198
Moderate
Prices estimated as of March 2026. Costs vary by region, vehicle, and shop.
P0455 on Volkswagen Polo
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.
What causes P0455 on a Volkswagen Polo?
Volkswagen PoloN80 purge valve failure
Volkswagen PoloBrittle EVAP hoses near the fuel tank on TSI models
P0455 on Skoda Fabia
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.
What causes P0455 on a Skoda Fabia?
Skoda FabiaCharcoal canister damage from road salt and debris
Skoda FabiaLoose fuel cap after refuelling
P0455 repair cost for Skoda Fabia
Estimated costs for Skoda Fabia ownersadjusted lower than average due to Skoda-specific parts pricing
Repair
Parts Cost
Labor Cost
Total Estimate
DIY Difficulty
Replace or re-seat fuel cap
€10–€38
€0–€0
€10–€38
Easy
Replace disconnected or split EVAP hose
€10–€48
€29–€114
€38–€162
Easy
Replace charcoal canister
€57–€266
€57–€190
€114–€456
Moderate
Replace vent valve or purge valve
€19–€95
€29–€114
€48–€209
Moderate
Prices estimated as of March 2026. Costs vary by region, vehicle, and shop.
Related diagnostic codes
These codes are often seen alongside P0455 or indicate related issues:
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.
