While parked in our garage tonight, I heard a whirring motor sound coming from our Prius v. It seemed to be coming from under the car toward the rear about halfway between the two rear wheels. I think I've heard this sound before, but tonight it went on for many minutes (5ish). I finally couldn't stand it anymore so I turned the car on by pushing the start button twice without holding down the brake pedel. This stopped the whirring sound, and when I turned the car off, the sound stayed off. Any idea what this is and if it should be going on for 5+ minutes while the car is off?
This is a normal sound. The car is running a test of the evaporative emissions systems. In the owners manuals it talks about this particular noise. It also mentions that it takes place several hours after shutting down the car.
