Stuck or failed canister vent valve; Blocked vent filter or vent hose (dirt, spider webs, mud); Broken wire or poor connector at the vent valve; Damaged charcoal canister.

How much does it cost to fix P0446?

Usually 50–300 € at an independent workshop in Europe, depending on which part is at fault.

P0446 EVAP vent control circuit

What P0446 means

The engine control unit cannot properly control the evaporative emission (EVAP) vent valve, which opens the charcoal canister to fresh air and seals it during leak tests. The leak test cannot run correctly while this fault is present.

P0446 is a generic SAE J2012 code: it means the same on every make. The exact cause still depends on the car, so read the freeze-frame data before replacing parts.

At a glance

Severity: Low
Typical repair cost: 50–300 €
Workshop time: 0.3–1.5 h
Repair difficulty: Easy
DIY possible: Yes
Check engine light: Yes
Affects emissions test: Yes

Parts and labour at an independent workshop in Europe. Main dealers charge more; the cause decides the bill, not the code.

Symptoms

Check engine light on
Fuel pump nozzle clicking off early when refuelling
Usually no change in driving

Common causes

Stuck or failed canister vent valve
Blocked vent filter or vent hose (dirt, spider webs, mud)
Broken wire or poor connector at the vent valve
Damaged charcoal canister

Can I keep driving with P0446?

This is a low-priority fault. You can keep driving and have it checked within one to two weeks.

What to check first

Locate the vent valve near the canister or fuel tank and inspect its connector
Check the vent hose and filter for blockage
Command the vent valve with a scan tool or apply voltage to confirm it clicks
Replace the vent valve or canister as needed

Related codes

Data: TORKO fault-code catalogue, built on OBDex (CC0-1.0) and reviewed against workshop practice. Informational only — it does not replace a diagnosis by a mechanic.
Updated: 2026-10-24