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Weird sound, not the normal one, from Prius when turning off

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Wishes2013, Jan 7, 2023.

  1. Wishes2013

    Wishes2013 Junior Member

    Joined:
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    2008 Prius
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    Hello All,
    I have a Prius 2008, and recently I can hear a weird sound after turning off the engine. This sound is not like the normal sound which I used to hear previously which I think is related to the pump.
    I feel like the pump is struggling to do what it's supposed to do.
    I recorded the sound and added a link to it, it is like zzzzz sound.

    Note: sometimes I hear the sound when turning on the car, but for very few seconds.



    Any help is appreciated!
    Thanks
    Wishes
     
  2. bisco

    bisco cookie crumbler

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    Plug-in Base
    have the 12v load tested. could be the brake booster, or maybe a coolant pump
     
  3. mr_guy_mann

    mr_guy_mann Senior Member

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    Listen for it the next time you turn the car off. Then press the brake pedal several times - does the brake pump sound the same or not?

    It could be the Coolant Heat Storage pump. It runs a few seconds after shutdown, and after going ready but before running the ICE (the ICE will start almost immediately if the heater is on when going ready). It usually is noisier in cold weather when it starts wearing out.

    Posted via the PriusChat mobile app.
     
  4. Wishes2013

    Wishes2013 Junior Member

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    Vehicle:
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    Thank You for your responses, I had the car checked by a mechanic, and after listening to the sound, he said it is "coolant Heat pump" and there is no big harm if I leave it without replacement now; however, today (after two days) the sound disappeared, but the Hybrid system and check engine alerts appeared!
    I had the car tested by another mechanic, he read the error codes, then told me it is the Hybrid battery! and that the "coolant Heat pump" is running fine.
    so it seems I am going for a battery replacement now...
     
    bisco likes this.
  5. bisco

    bisco cookie crumbler

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    please post the trouble codes here before dropping a ton on a new battery. the battery does cause any sounds, but some mechs cause a load sucking sound in your wallet