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2004 ominous noise- brakes? actuator?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by priusrust, Dec 5, 2023.

  1. priusrust

    priusrust Member

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    2004 Prius
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    looking to diagnose: When I start car up and begin to drive....an ominous rumbling noise when I apply brakes:-.....BBBRRRRRRR.....been going on a while
    After a short while, noise disappears.

    I had actuator replaced not very long ago...BUT was replaced with a used one. Since the original where known to have a short life due to defect..... I cant rule out that once again its bad. BUT...no idea what the noise is...just guessing. front brakes been checked recently- no issue
    thanks!
     
  2. bisco

    bisco cookie crumbler

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    where does it sound like it's coming from?
     
  3. priusrust

    priusrust Member

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    center/ mid-front ....ish

    I did have one of those knock off CAT shields covering cat with some questionable material left dangling that might cause noise....BUT this happens only when I brake.....clearly part of braking system. Would this be actuator going bad?
     
  4. bisco

    bisco cookie crumbler

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    It’s hard to know from your description. Usually you get the frequent pump buzzing or quacking kind of sound. can someone listen under the hood while you step on the brake?
     
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