Skip the auto shop - Our mechanics make house calls

Q: Charcoal can gas leak

asked by on

My charcoal canister is filling up with liquid gas and leaking out the bottom. I was told it was possibly a purge valve? Ive had to replace the can twice already.

My car has 163675 miles.
My car has an automatic transmission.

A: All modern cars are equipped with an Evapor...

All modern cars are equipped with an Evaporative Emission Control (EVAP) system. The EVAP system prevents fuel vapors from the fuel tank from escaping into the atmosphere. The EVAP system collects and temporarily stores the fuel vapors in the charcoal canister. The charcoal canister is filled with activated carbon pellets that can absorb the fuel vapors. When the engine is running, the fuel vapors are purged from the canister and burned in the engine.

The vent control valve (solenoid) controls the flow of outside air in and out of the charcoal canister. One side of the vent valve is connected to the charcoal canister. The other side is connected to the vent hose that has a filter or screen at the end and is attached to the car body or frame. In some cars, the vent valve is attached to the canister. In others, it’s installed separately near the canister.

The vent valve is controlled by the engine computer. Normally the vent valve is open. It closes when the engine computer tests the EVAP system for leaks. If a leak in the EVAP system is detected, the Check Engine Light will illuminate on the dash and the trouble code related to the problem will be stored in the engine computer. I would recommend having a professional, such as one from YourMechanic, take a look at your car to properly diagnose and replace your solenoid.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Does this car have a PCV valve?

All cars that have internal combustion engines have Positive Crankcase Ventilation (PCV) valves. On your car, the PCV valve is at the top of the engine in the valve cover. It is pressed into a rubber grommet. You will see...

Q: Car not accelerating and doesn't always start

Your issue sounds like it could be a failed fuel pump in its last moments of life. With lack of fuel the vehicle will run very poorly and will not be able to accelerate and won't be able to run...

Q: Check Engine Light on and off, reader gives P0446 error 1999 Toyota Corolla

Hello - the P0446 code is an indication that the evaporative emissions purge valve electrical circuit has had a loss of electrical power to the vent valve that allows fresh air to enter the evap cannister. This could be a...

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.