Diagnostic help- strange whirring noise?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by gen2enjoyer, May 11, 2026 at 8:25 AM.

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  1. gen2enjoyer

    gen2enjoyer New Member

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    Car runs and drives fine but I often find the inverter coolant is low (possible leak?) and after driving for a bit there's a whirring noise that goes away at stoplights. Also occasionally makes sloshing noises after powering it off.

    Any thoughts/input are greatly appreciated, thanks in advance.
     
    #1 gen2enjoyer, May 11, 2026 at 8:25 AM
  2. bisco

    bisco cookie crumbler

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    welcome!
    how many miles and how long have you owned it?
    definitely a leak somewhere
     
    #2 bisco, May 11, 2026 at 1:45 PM
  3. Tombukt2

    Tombukt2 Senior Member

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    The inverter coolant path is not very complicated tracking a leak should be quick . Invert fluid not flowing and that system getting hot could produce strange noises. And for sloshing . After car cools move plastic re. I've radiator cap. When you remove the cap you should see coolant or water standing proud at the top of the neck almost ready to dump on the ground what do you see when you remove your radiator cap at a cool state of the vehicle . If you can look down that black plastic filler neck and see nada that maybe part of sloshing . Systems needs be FULL.
     
    #3 Tombukt2, May 11, 2026 at 2:10 PM
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