Automotive Forums

Recently, I've had a problem with my wagon and was wondering if anyone had the same thing or knew what it was. The problem is that even after I turn my car off, it seems like my motor still runs. Sometimes longer than other, but every time after I turn off the ignition. It sounds like the engine is revving up, even though it is off. Has anyone else had the same problem or have any ideas as to what might cause this to happen? Thanks in advance.