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Extreme rattle under the hood only in park

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by TripleFlipBacon, Aug 9, 2022.

  1. TripleFlipBacon

    TripleFlipBacon New Member

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    Yeah so only in park, there is a really loud constant rattling (under the hood) but if i put it in drive with my foot on the brake the rattliing immediately stops, also sometimes if i move the car slightly forwards or backwards, then put it in park, the rattling stops.

    Also it doesnt rattle at all in neutral regardless of car position

    What is going on I have looked many places online and could not find a similar scenario.
     
  2. JC91006

    JC91006 Senior Member

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    When was the last time you serviced your car? Oil change, spark plug and coils?
     
    SFO likes this.
  3. Mendel Leisk

    Mendel Leisk Senior Member

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    You’ve popped the hood? Just saying because after one dealership visit: loud rattle, popped the hood, and found the hood support rod loose.
     
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  4. TripleFlipBacon

    TripleFlipBacon New Member

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    I changed all spark plugs maybe 2 years ago, coils never touched, oil change regularly (it does get low sometimes it leaks or something)
     
  5. JC91006

    JC91006 Senior Member

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    "it does get low sometimes"

    Well that may be the culprit here, a damaged engine
     
  6. Tombukt2

    Tombukt2 Senior Member

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    God I would hope not I seen Jen twos that use two were possibly three quarts of oil between the 7500 to 10,000 mi change. Of course these cars all have over 250,000 on them and usually it's not quite that bad. But I would hope and bad engine is not a possibility here but it's a possibility anywhere and it doesn't do it in neutral and only in the car in certain positions and something really silly is pretty loose shield under the car the ones that are way forward right down near the cat or something can't see from here.
     
  7. Mendel Leisk

    Mendel Leisk Senior Member

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    How low, ie seeing some oil on the dipstick still, or nothing?
     
  8. TripleFlipBacon

    TripleFlipBacon New Member

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    I forgot to mention, it only rattles in park if its charging the battery, if the battery doesnt need to be charged it will run normal no noise at all, but as soon as the battery gets low enough to charge it starts to rattle (in park)
    Usually there is oil on the dipstick, any my car has 305,000 miles on it its been doing this rattle thing for like 70k+ miles (I drive a lot)
     
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  9. bisco

    bisco cookie crumbler

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    so it's only rattling when there's a load. could just be something loose. open the hood and video it for posting here. see if you can detect the area of rattle
     
  10. Another

    Another Senior Member

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    What does ‘regularly’ mean?

    Also, when you changed the plugs, did you check the PCV valve?
     
    #10 Another, Aug 12, 2022
    Last edited by a moderator: Aug 12, 2022