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Buzzing noise from rear in the middle of the night....

Discussion in 'Gen 2 Prius Main Forum' started by sorka, Jun 8, 2011.

  1. sorka

    sorka Active Member

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    Last week, I went out to my garage to investigate a motion sensor event that shouldn't have occured. It was about 3:00 in the morning. The Prius had been powered off for probably 8 hours or more.

    I suddenly heard a strange buzzing noise coming from the rear. Too concerned with security due to the motion sensor event, I didn't spend a lot of time trying to figure it out, but it continued the entire time I was in the garage.

    The next morning, when I came back in, it was fine.

    The noise sounded pump like. In fact, it was somewhat similar to the coolant/thermos pump noise that comes from the front of the car, but about 2 or 3 times the frequency, hence it sounded more like a buzz.

    I have no clue what this could be.
     
    #1 sorka, Jun 8, 2011
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Five hours after the Prius is powered down, a pump runs to verify integrity of the fuel tank system. Perhaps this is what you heard.
     
    #2 Patrick Wong, Jun 8, 2011
    1 person likes this.
  3. qbee42

    qbee42 My other car is a boat

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    Or maybe the Prius was getting a blow job from the lawn mower. That's probably what triggered the motion event.

    ;)

    Seriously, though, Patrick has this one figured out. The fuel system checks for leaks after several hours of inactivity, which usually means the middle of the night.

    Tom
     
    #3 qbee42, Jun 8, 2011
  4. sorka

    sorka Active Member

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    Awsome! That had to have been it. Thanks for figuring that out!
     
    #4 sorka, Jun 8, 2011
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