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Vibration under hood during cold morning start

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Rich12, Feb 5, 2014.

  1. Rich12

    Rich12 Member

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    I'm experiencing vibration somewhere under the hood during start. I recently replaced the serp. belt and think it could be over-tensioned. Possible? Dangerous? Or just the new belt needs to stretch?
     
  2. JC91006

    JC91006 Senior Member

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    OMG Rich!! You should have let the dealer handled this for $35......
     
  3. Rich12

    Rich12 Member

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    Dude. Chill. If it's over-tensioned it's an easy enough fix. Just wanted some input on the symptoms.
     
  4. JC91006

    JC91006 Senior Member

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    ok, I'm chilling.......the vibration goes away?
     
  5. JC91006

    JC91006 Senior Member

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    When the ICE engine kicks in, many times when you're not moving, you may feel a vibration. But I'll let others ring in about the belt tension.
     
  6. Patrick Wong

    Patrick Wong DIY Enthusiast

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    If the vibration in fact was associated with the serpentine belt, this would more likely be the result of a loose, under-tensioned belt flapping around.

    I really doubt that any engine vibration is associated with the serpentine belt. More likely, any unusual vibration is associated with a loose engine mount or a misfire situation that goes away after the engine has warmed up a bit.

    When you exert a force of 22 lb at the center of the long run of the serpentine belt, the belt should deflect ~0.4".