I have a 2008 Corolla S and the last couple days I've noticed after coming home that after I park the car and come back after a couple hours I hear a strange electical motor noise coming from the rear of the car. It sounds the loudest when I lean down by the rear wheel. I can stop the noise by turning the car on, letting it run for a couple seconds, and turning the car off again. I'm not having any issues with the car, just this noise is worrying me.

I think the Corolla manual talks about this noise - has something to do with the fuel system - checking for gasoline vapors after the car has sat for a while. If your noise is the same thing, the manual said not to worry about it.