5 Symptoms of a Faulty Engine Vapor Canister Filter

Also known as an evaporative emissions control canister (EVAP), your engine's vapor canister filter stores escaping vapors from your fuel system. Filled with activated charcoal, this plastic, rectangular component limits harmful emissions and supports good fuel economy. If it breaks down, your check engine light will turn on. You'll also notice several significant changes in engine performance. The following are five signs of a faulty engine vapor canister filter to watch out for.

1. Pungent Gas Odors

If you catch a whiff of gas while standing near your car, you might have a leak in your fuel line, fuel injector, or gas tank. However, if you smell pungent gas odors around your car after a short drive or within your vehicle's cabin, the vapor canister filter is a likely culprit. When this component no longer catches and retains fuel vapors, gas odors become overwhelming.

2. Difficulty Filling Your Fuel Tank

When fueling up, air inside your fuel tank moves out to create room for gas. The vapor canister traps fuel vapors during this process so that they don't escape into the outdoor air. If working correctly, the EVAP system then moves these vapors to the engine for burning. This process is known as purging.

When engine vapor canister filters are clogged or no longer working correctly, purge valves stays closed and air displacement never occurs. This causes fuel pumps to registers tanks as being full even though they're only partially full or completely empty.

3. Poor Fuel Economy

If you can still fill your tank with a faulty engine vapor canister filter, your fuel won't last for long. The gas that you're smelling around your vehicle is vaporized fuel that your engine can never burn.

4. Failed Emissions Tests

It's impossible to pass an emissions test with a faulty vapor canister filter. Vehicles will always produce more than the maximum allowable emissions limits for exhaust as established by the U.S. Environmental Protection Agency (EPA) when their EVAP systems aren't functioning properly.

5. Trouble Starting

A faulty vapor canister filter can also cause start-up issues. Filter problems impact the performance of the purge valve and the flow of fuel vapors to the engine. If your vehicle does start up, you'll likely experience rough idling or all-around poor engine performance until the issue is resolved.

We help drivers keep their engines running smoothly. With our state-of-the-art repair shop, cutting-edge diagnostic tools, and seasoned mechanics, we can find and fix problems with your auto's EVAP system in no time. If your check engine light is on and your fuel economy has declined, contact Custom Complete Automotive today!