[FONT=verdana, geneva, helvetica]Definition: A storage device in the evaporative emissions control system. It is a small cylindrical or rectangular container that contains activated charcoal particles. The charcoal traps gasoline vapors from the fuel tank (and carburetor on older vehicles). Later, the vapors are purged and drawn into the engine when the vehicle is being driven. [/FONT]
I ditched mine on my 1987 stang and had no problems. I also disconnected the hard line at the valve on fuel tank. I believe cannister filters fuel vapors from fuel tank. Maybe its a F**K NO on a new mustang not sure.