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Whirring noise after I shut it off and remove the key

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by impreza, Apr 4, 2004.

  1. impreza

    impreza New Member

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    After I shut the car off I hear a quiet noise. It lasts about 30 seconds and seems to be coming from the engine. What is it?
     
  2. Lectricar

    Lectricar New Member

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    Coolant being sucked into a thermos in the engine...it assures a warmed up car
     
  3. impreza

    impreza New Member

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    WOW! I heard something about water being kept "HOT" for the next startup and wondered how that worked.

    Those guys thnk of everything!

    How long does that water stay hot?
     
  4. starla30

    starla30 New Member

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    "To optimize engine and emissions performance, the new Prius uses an electric water pump and insulated hot water storage thermos ('HC absorber'). The intent is to ensure the engine is warm before the hybrid demands power from it. The claim is that the water storage system can maintain the water temperature above 85 degrees for 3 days."
     
  5. impreza

    impreza New Member

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    Thanks for the info.
     
  6. HTMLSpinnr

    HTMLSpinnr Super Moderator
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    Actually the HC absorber was used on the '01-'03 Prius, and was a special catylitic converter which absorbed HydroCarbons (HC's) until the cat was warmed, at which point they were burned off. This was later applied to the '04 Camry PZEV.

    The thermos in the '04 heats the engine so that it doesn't generate as many unburned HC's while it's below normal operating temp.

    I would have liked to have seen both in the '04, but alas.

    They say that the Thermos can keep the coolant at near boiling overnight, and quite warm for several days.

    -Rick
     
  7. jeffrey

    jeffrey New Member

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    I get the same noise, but I've noticed that after a few more minutes (perhaps 3 or 4) I often hear another rumble/slight grinding noise coming from somewhere under the passenger compartment. Something to do with the drive battery I suppose?

    I was looking in the manual last eve to see if I could find it, but have not as yet. Anyone know?

    Thanks :)
     
  8. HTMLSpinnr

    HTMLSpinnr Super Moderator
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    Brake pressure pump.

    I hate to say this, but these topics have all been covered before - search through the forums and you'll find that we've already gone into detail on this.

    -Rick