2012 Gen 3 Prius. Engine shaking when accelerating.

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Darth_Eric, Mar 14, 2025.

  1. Darth_Eric

    Darth_Eric Junior Member

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    2012 Prius
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    II
    2012 Toyota Prius 125K miles, well maintained and taken care of. Just started getting some shuddering and shaking coming from the engine it feels like when accelerating. My coolant levels are solid and, have kept up on regular oil changes. My only guess would be EGR cleaning? maybe its clogged or Engine mounts? or Water Pump. I've cleaned the battery fan and changed the spark plugs myself in the past year. I've also noticed lack of power i know thats relative with the prius but seems to be more then usual. Any ideas on what it could be? No check engine light. Also it used to burn a lot of oil when i lived in texas and drove a lot more. Now i moved back home to Seattle and it doesnt seem to burn any oil at all at least not that ive noticed
     
    #1 Darth_Eric, Mar 14, 2025
  2. Grit

    Grit Senior Member

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    egr was never cleaned then it wasn’t “well maintained. Git r done.
     
    #2 Grit, Mar 14, 2025
  3. bisco

    bisco cookie crumbler

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    Might as well start with the egr circuit, you need to do it anyway, if it isn’t too late.
    Maybe do a leak down test first?
     
    #3 bisco, Mar 15, 2025
  4. rjparker

    rjparker Tu Humilde Sirviente

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    Coolant loss is undetectable at first; Borescope is definitive; others can provide false negatives

     
    #4 rjparker, Mar 15, 2025
    bisco likes this.
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    Info on EGR cleaning and head gasket remediation in my signature (on a phone turn it landscape to see signatures).

    Neglected EGR cleaning and head gasket failures are like peanut butter and jam with the 3rd gens, and v’s. :)
     
    #5 Mendel Leisk, Mar 16, 2025
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