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Buzzing/Rattling sounds at low speeds

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by ou_chot, Jul 19, 2011.

  1. ou_chot

    ou_chot New Member

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    Just purchased 2007 Prius Touring model w/ Package 6. Wonderful car.

    Quick question: Is it normal to hear a buzzing/rattling noise when stopping at low speeds or starting at low speeds?

    It seems to be coming from the drivers side. Doesn't happen every stop/start.

    Thanks for your help.
     
  2. seilerts

    seilerts Battery Curmudgeon

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    That is the accumulator pump in the brake actuator. Perfectly normal.
     
  3. ou_chot

    ou_chot New Member

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    Is it normal for the buzzing to happen several times during a given ride?
     
  4. seilerts

    seilerts Battery Curmudgeon

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    Yes, it is normal. The pump maintains pressure in the hydraulic brake system. An electric pump is necessary because a vacuum booster pump would not work, since the engine is not always running.