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Rattle/Knocking

Discussion in 'Prius c Technical Discussion' started by 15PriusC, Feb 4, 2024.

  1. 15PriusC

    15PriusC New Member

    Joined:
    Jun 17, 2023
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    Location:
    West Virginia
    Vehicle:
    2015 Prius c
    Model:
    Two
    Howdy everyone,
    I know this is a dead horse but I’ve never seen it addressed on a c with the 1.5. I bought my 15 Prius with 161k miles, 9 months later I have 185k and have been happy with the car. I first noticed when it started to get cold and it would sit over the weekend especially if it would rain the engine would shake and rattle for about 30seconds on first start up. It was bad sounded like it was gonna blow. Now that it’s cold it doesn’t do anything near that bad but every cold start I get a loud knocking/rattle for about 3seconds. I change the oil every 5k miles using Toyota filter. It runs fine and hasn’t given a check engine light or any other problems. Just nervous because it sounds like a bottom end knock. Any thoughts?
     
    #1 15PriusC, Feb 4, 2024
  2. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
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    38,644
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    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Not at all. Prius c has a Gen 2 engine; Gen 3 is the horse meat factory, for cold-start rattles.

    Seems like high relative humidity is a factor: happens more in rainy conditions, less when cold.

    Keep an eye on engine coolant level stable in the reservoir.

    Take oil filler cap off and check for white froth.
     
    #2 Mendel Leisk, Feb 5, 2024
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
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    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    #3 bisco, Feb 5, 2024
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