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Clicking Noise on Start AND...

Discussion in 'Gen 2 Prius Main Forum' started by Marvinh, Dec 27, 2008.

  1. Marvinh

    Marvinh Marvin

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    ... when going from 'Park' to Drive'. I did a search on the forum and I know that the clicking noise on startup is probably the coolant pump putting coolant back into the engine on COLD startup.

    But I sometimes hear a few clicks when I switch from 'Park' to 'Drive'. Like at a traffic light.

    Does anybody have an explanation for the the clicks from 'Park' to 'Drive'?

    Thanks! Marvin
     
    #1 Marvinh, Dec 27, 2008
  2. dogfriend

    dogfriend Human - Animal Hybrid

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    When you select D from P, there is a parking "pawl" that must disengage from the transaxle so it can move. (In P, it is locked, in all other positions is is disengaged). I think that may be the clicking that you can hear.
     
    #2 dogfriend, Dec 27, 2008
  3. Marvinh

    Marvinh Marvin

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    Hi. Thanks for your reply. However, its the same clicking noise I hear when I start from a cold start.

    Marvin
     
    #3 Marvinh, Dec 27, 2008
  4. dogfriend

    dogfriend Human - Animal Hybrid

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    Maybe what you are hearing is the brake accumulator pump? Some people describe it as a rattlesnake sound that comes from the dash area. It will make the sound when the brake fluid pressure is low and you step on the brake pedal. It doesn't make the sound every time you press the pedal; just when the pressure has dropped below a certain threshold - then it makes the sound for a second or two while it rebuilds pressure. Usually about every 3rd or 4th time you press the pedal.

    So it can make that sound when you press the brake to start the car and also when you press the brake to shift from P to D.
     
    #4 dogfriend, Dec 28, 2008
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