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Whining sound after shut down

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by nctalkinghead, Feb 14, 2007.

  1. nctalkinghead

    nctalkinghead New Member

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    My '05 w/25k has developed a "whining" sound after I turn off the power. I know there is some sort of device that runs prior to and after I hit the power button. I've always heard that sound, but in the past couple of months is has started this "whining" sound. I'm going in Friday for my 25k oil change, etc and wondered if I might use the group's experience to help identify this problem to the technician. Many thanks in advance!
     
  2. IsrAmeriPrius

    IsrAmeriPrius Progressive Member

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    <div class='quotetop'>QUOTE(nctalkinghead @ Feb 14 2007, 02:28 PM) [snapback]390473[/snapback]</div>
    It's the coolant transfer pump. Here is one thread where the problem has previously been discussed: Screaming coolant pump, Dealer replacing 1 of my 2 coolant pumps
     
  3. nctalkinghead

    nctalkinghead New Member

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  4. jayman

    jayman Senior Member

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    When you power down the car, about a minute later there will be a soft "phwoosh" sound, then a soft rattling/clicking sound. That's the brake system purging itself and the electric boost pump building pressure again.

    A whining or whirring sound is usually the coolant transfer pump. One with awful bearings will make more of a groan or howl sound.