Toyota Prius 2011 198k miles weird noise

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Kelvin Boral, Nov 25, 2025 at 9:44 PM.

  1. Kelvin Boral

    Kelvin Boral New Member

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    Location:
    Orlando
    Vehicle:
    2011 Prius
    Model:
    Two
    Hello, does anybody knows what this sound might be? It seems to come close to the hybrid system and not the engine. This happen only when the car is in park and I see the engine recharging the battery or when I am driving slowly…

    No is not the cat under the car
     
  2. Mendel Leisk

    Mendel Leisk MMX GEN III

    Joined:
    Oct 17, 2010
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    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Did you pop the hood for a better listen?

    A 3rd gen with 198k miles, the first thing that comes to mind is head gasket letting go, coolant leaking into the cylinders. That's regular as clockwork.