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2012 Ct200h cylinder 3 misfire

Discussion in 'Gen 3 Prius Technical Discussion' started by akgyger, Dec 30, 2020.

  1. akgyger

    akgyger Junior Member

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    Other Hybrid
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    Cheers priuschat,

    had my first major issue with my third gen, 116k on the odometer, flashing CEL, OBD2 scanner shows cylinder 3 misfire. Sounds like a skeleton whacking off inside a filing cabinet.

    Religiously changed oil at factory specified intervals, dipstick looks perfect, and my coolant is oem and at proper levels. In the summer of 2020 at 100k I replaced the spark plugs with denso (can’t remember the model, can’t guarantee they’re double iridium) and this car has been perfect up until today.

    started scrambling other posts on PC about similar issues, but nothing really gave me an “aha!” In terms of diagnosing my issue.

    Am I right to follow this trial and error flowchart? Double iridium denso spark plugs > new denso coil pack set > denso fuel injectors

    hoping to avoid a dealership service as I am handy with mechanical work but this is my first Toyota service, I come from a world of Volvo repair.

    thanks for reading, and I appreciate any words of wisdom or experience. Plan to start wrenching and diagnosing tomorrow.
     
  2. Raytheeagle

    Raytheeagle Senior Member

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    Welcome to Prius chat(y).

    One item in this space worth considering is an egr circuit cleanse;).

    Another item is to make sure the engine coolant level is stable.

    Give those two items a review as they are more common than COPS going bad(y).
     
  3. Mendel Leisk

    Mendel Leisk Senior Member

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    #3 Mendel Leisk, Dec 31, 2020
    Last edited: Dec 31, 2020
    Raytheeagle likes this.
  4. akgyger

    akgyger Junior Member

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    Other Hybrid
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    My ct is alive again and well (for now)

    I’m thinking I got a bad batch of denso spark plugs earlier this summer. Confirmed that cylinder 3’s “double tipped” was missing its extra pip on the bottom of the spark plug. I have a new set of denso TT 4711 and a new set of ignition coils installed and everything is running smooth after a few test drives.

    I plan on doing the intake cleaning when the weather gets nicer and will take the bad flywheel thread and other points of failure mentioned into suggestion if I notice any further issues