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Annoying fluttering sound from ventilation fan

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Sun Lion, Jun 14, 2021.

  1. Sun Lion

    Sun Lion New Member

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    Hi there!

    My Gen 2 Prius has just recently begun making an annoying fluttering sound when the climate system is in use.


    At low speeds the noise is slower, and at higher speeds the noise is faster. It only stops if I turn off the climate system.
    I removed the glove box to see what I could find, as well as to replace the cabin air filter. Upon further inspection, the fluttering noise is from the spinning component of the fan.

    Video


    Any ideas on what to be done to make the noise go away?

    I'm wondering if the spinning part just needs to be replaced due to perhaps the bearings being shot? If so, I may need to take it into a shop for that as it seemed tricky to get that component in/out.

    Thanks so much for your help and guidance!!


    PS, this is my first post! What an amazing community of resource here :) Grateful.
     
  2. rjparker

    rjparker Tu Humilde Sirviente

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    I would try a can of ac coil cleaner injected from the condensate drain.
     
  3. bisco

    bisco cookie crumbler

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    are you sure there isn't any debris in between the fan blades and the sides?
     
  4. sam spade 2

    sam spade 2 Senior Member

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    WHAT ??
    That makes no sense at all.
     
  5. mr_guy_mann

    mr_guy_mann Senior Member

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    My first thought is that some sort of debris made it past the cabin air filter and is now "stuck" in the fan/ blower. Usually isn't too difficult to remove the blower motor assembly, clean it out, and put it back.

    Posted via the PriusChat mobile app.
     
  6. JC91006

    JC91006 Senior Member

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    I would reach my hand in the fan and see if I can clear out some debris.

    Alternatively you can remove the fan and just clean it out completely.
     
  7. pasadena_commut

    pasadena_commut Senior Member

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    It does sound quite a bit like a worn fan bearing to me. With the car completely off see if you can give one of the blades a good push with a finger to set it spinning. If the bearing is in good shape it should spin for a "reasonable" time (at least many seconds) with little or no noise. If it stops rapidly, especially if it doesn't even complete one turn, or is noisy then it is most likely the bearing. To do that test you will need to pull out the filter.



    Also see:
     
  8. fotomoto

    fotomoto Senior Member

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    My original gen1 RAV4 would suck in napkins from the glove box if they were left loose on top of all the other things.
     
  9. Krokettenslayer

    Krokettenslayer Junior Member

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    Did the sound start gradually or did it happen all of a sudden? If so I would suggest using one of these to vacuum out any debris that could have fallen next to the fan.
     

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  10. Mendel Leisk

    Mendel Leisk EGR Fanatic

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  11. dolj

    dolj Senior Member

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    If it were mice, I'd have thought it would be more of a squeak, no?
     
    Mendel Leisk likes this.
  12. ChapmanF

    ChapmanF Senior Member

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    When my dad's Hyundai had a mouse nest in the fan, it shook the whole dash like an unbalanced washing machine.