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.
DTC/P0455·Volkswagen
P0455 on Volkswagen: Causes, Symptoms and Fix Cost
Quick Answer
Moderate SeveritySafe to drive (short-term)Volkswagen
P0455 on a Volkswagen 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.
Repair cost on Volkswagen€10 - €480
What does P0455 mean on a Volkswagen?
Volkswagen Polo
2005-2024The 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?
Beyond the generic causes listed on the main P0455 page, these are the Volkswagen-specific patterns we see most often:
Volkswagen PoloN80 purge valve failure
Volkswagen PoloBrittle EVAP hoses near the fuel tank on TSI models
How to diagnose P0455 on a Volkswagen with OBD2
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 on a Volkswagen? (EUR)
Estimated repair costs on a Volkswagen (Volkswagen costs align with the average for this code across makes).
Prices estimated as of May 2026. Costs vary by region, vehicle, and shop.
Related codes that often appear with P0455 on Volkswagen
These codes commonly cluster with P0455 on Volkswagen vehicles:
FAQ: P0455 on Volkswagen
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.
Looking for the full P0455 reference (all makes, full diagnosis flow, complete repair cost matrix)?
See the main P0455 guideSkanyx · Volkswagen
Diagnosing P0455 on your Volkswagen?
Connect any Bluetooth OBD2 adapter, scan for codes, and get AI-powered diagnostics with severity ratings and repair cost estimates.
Download Skanyx