WESLACO – Topping off your gas tank is an expensive habit that is also bad for the environment.

“It's really bad for the environment. It's really bad for the car. What it really does is it overwhelms the evaporative system in the vehicle,” says Texas Department of Transportation spokesperson Octavio Saenz.

The Environmental Protection Agency says once your tank is full, there’s no way to fit any more gas in the tank.

The excess vapors will feed back into the station’s tank or escape into the environment.

Watch the video above for more information.