Symptoms Of a Bad Canister Purge Valve

The liquid fuel kept in the fuel tank has a built-in propensity to rapidly evaporate, and high temperatures accelerate the process. To do this, a mechanism was created to stop gasoline vapours from the tank from escaping into the atmosphere. The Evaporative Emission Control (EVAP) system of an automobile is absolutely dependent on this mechanism, which is referred to as a canister valve. The purge valve canister on the EVAP controls how much fuel vapour can escape from the carbon canister.

When the car starts at its normal speed, the EVAP system enables the release of these vapours into the engine. The purge valve regulates the passage of these vapours. The purge valve was initially controlled by vacuum, but in new car models, it is controlled by the electronic control unit (ECU). The issue arises when the purge valve starts getting stuck and doesn’t open on time.

Well, in this article I’ll be discussing the symptoms of a bad canister purge valve.


What are the symptoms of a bad canister purge valve?

Symptoms Of a Bad Canister Purge Valve

Failed emission test

The vapour tank flush valve, as you are already aware, is in charge of directing fuel vapours to the engine. By doing this, harmful hydrocarbons are kept from escaping the tailpipe. The gasoline vapours won’t be forced back into the engine if the valve is stuck closed as opposed to open. Instead, they will emerge directly out of the exhaust pipe of the vehicle, producing substantially higher emission levels. Therefore, if your purge valve were to stop working, it wouldn’t be able to guide those fuel vapours and keep them from fleeing your car. When you take your emissions test and fail it, you will learn this the hard way. If this occurs, ask the mechanic to examine the exhaust valve to see if that is the component that caused the failed emission test. If it is worn out or harmed, it needs to be replaced right away.

Check Engine Light Is On

The check engine light is the first indication that anything is wrong with your canister purge valve. Your car’s computer manages your canister purge valve, allowing it to track its operation. The check engine light on your automobile will come on if the computer senses higher or lower purging from the valve than is normal. Along with other EVAP codes, the error codes P0441 and P0446 are frequently encountered. Make careful to take your automobile to a qualified mechanic who can help diagnose the issue if your check engine light comes on.

Poor engine performance

When the valve is stuck open, more air than necessary enters the vehicle’s system. That implies that the car is not putting enough fuel into the engine each time the throttle is depressed. When driving at low RPMs, these impacts are most perceptible.  Don’t anticipate a pleasant ride if the purge valve is damaged but the car will start. The performance of your engine will be reduced. In other words, when the accelerator pedal is depressed, the engine cannot produce enough power to generate the necessary acceleration. When moving uphill or attempting to pass another car, this is more obvious.

Lower Gas Mileage

Your gas mileage could suffer if your canister purge valve is not opening properly. The reason for this is that you will lose some of the fuel that is typically used since the vapours that your car usually utilizes in combustion will locate the EVAP canister and eventually be released into the environment.

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You can notice a rough or inconsistent idle, sporadic stalling, decreased fuel efficiency, and an illuminated check engine light when the canister purge valve in your car’s emissions control system is broken. These concerns frequently point to faults with the fuel vapour management system and emissions control system.

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