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Loud bumping sound when completely disengaging brakes from a stand still

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by hopesong, Aug 30, 2016.

  1. hopesong

    hopesong New Member

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    Hi PriusChat forums,

    My wife's 2007 Prius 2 is making a loud noise as soon as the brakes are disengaged completely. It only occurs when taking off from a stand still. Even at slow rolls it won't make the noise. It occurs without any use of the accelerator whatsoever, that is to say it is pertaining to brakes only.

    This is not a typical releasing of the brakes sound which sounds similar to a low pitched fart. Instead this is more like a bump or a bark and it only happens at the very moment the brakes are fully disengaged. It seems to be primarily coming from the right side of the engine compartment. It seems to also be accompanied by a lunging of the car going forward. The car has about 130,000 miles on it. Any idea what it could it be and what the costs of repair would be?

    Thanks in advance
     
    #1 hopesong, Aug 30, 2016
    Last edited: Aug 30, 2016
  2. JC91006

    JC91006 Senior Member

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    You might have a sticking caliper......check the glide pins, might need lubrication. The lunging is similar to you holding the footbrake and accelerator at the same time. Once you release the brake (the sticking brake), you lunge forward from the accelerator being pressed
     
    #2 JC91006, Aug 30, 2016
  3. hopesong

    hopesong New Member

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    Thanks for the reply.

    It occurs without any acceleration whatsoever. I should edit my post to reflect that.
     
    #3 hopesong, Aug 30, 2016
  4. JC91006

    JC91006 Senior Member

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    But you have a forward motion whenever you're in "D". Once you release the brake, you roll forward
     
    #4 JC91006, Aug 30, 2016
  5. andrewclaus

    andrewclaus Active Member

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    Yep, check for sticking caliper. Any brake shop can do that, no need to go to Toyota, and it should be minimal cost to repair.

    Do you use your parking brake regularly? Is it working correctly?
     
    #5 andrewclaus, Aug 30, 2016
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