P0446 Fault Code

Long Description

Fault code P0446 represents the presence of a fault within the evaporative emission control system (EVAP). It is logged when the engine control module (ECM) detects an issue with the EVAP vent control valve.

The EVAP system is required in modern cars to meet emission regulations that are mandatory in most countries. This system prevents fuel vapors from leaving the fuel tank and system and entering the atmosphere.

As EVAP systems are required in all modern cars, this error can come up in any vehicle. However, some of the most common brands to suffer from this issue are Audi, Kia, Volkswagen, and Jeep.

Other Signs of This Problem

There are very few symptoms of EVAP-related issues. The Check Engine light and the subsequent P0446 OBD2 code are some of the best ways to tell that there is an issue to address.

Another possible sign is the presence of the smell of fuel when your car is parked. This can be more noticeable if you park your car in a confined space like a garage. However, this is not a given and is typically very rare.

There may also be other EVAP-related codes being logged, which can indicate there is a leak rather than a specific issue with the vent control valve. Look out for codes like P0440 through P0454.

What Could Be The Problem?

Because the EVAP is a closed system, all causes are likely found within the system itself. Any damage or leaks within the fuel line in the EVAP system can cause issues like this.

Another very common cause of these issues is a faulty or poorly tightened gas cap. Any issues with the gas cap can result in a leak being detected, which can signal issues like this (shown as a P0446 fault code).

The vent control valve could also be the cause of this code being logged. Loose connections or wiring near this valve are a possibility. Other components in the EVAP system can also lead to similar outcomes.

Fixes

The majority of these fixes involve simply replacing faulty or damaged parts. It can also be as easy as ensuring the gas cap is properly tightened or that there is no leak present.

The first thing to do is also the easiest: check the vehicle’s gas cap. It is important that it is a factory gas cap that provides a proper seal when properly tightened. Ensure there is no damage or wear to the seal. Otherwise, this can be replaced easily in order to fix this P0446 fault code.

Ensure there are no leaks in the hoses, particularly near the vent control valve. If the vent control valve is faulty, replace it.

If any of the main components like the charcoal canister are damaged or leaking, replace them.

Check the wiring within the EVAP system for damage, as well as the connections.

Seriousness

Fault code P0446 can be considered low in severity. There is no real risk to the occupants of the vehicle or the vehicle itself.

However, if your vehicle is subjected to an emissions test, it is possible that it will fail. This can result in significant fines. For this reason, this issue should be fixed within a few weeks of it arising.