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Cylinder 2 doing some misfiring

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by C Clay, Aug 12, 2024.

  1. C Clay

    C Clay Member

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    Four
    I’m noticing some cylinder 2 misfiring, confirmed by the Scanner App. No codes or anything. Just by the data on the app, it appears to do it around 1300 RPM, yesterday on a 40 mile drive it did it maybe a dozen times.

    310,000 miles. Head gasket, plugs, EGR service - done around 50k miles ago.

    What to check? First thing I was thinking was maybe to swap the coils and see if the misfire goes somewhere else.

    While I’m there- I’ll do the EGR service (which I didn’t do myself, but I’m sure I can. Check the spark plugs also.

    Is that what you all would suggest as first steps? MPG is strong, it can be 50 if I drive it right. No loss of coolant, no hard starts.


    iPhone ?
     
  2. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Sounds sensible.
     
  3. C Clay

    C Clay Member

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  4. C Clay

    C Clay Member

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    I was able to clean everything up to the EGR valve, and replace the PCV valve at the same time. I was not able to do the EGR cooler. That was more patience than I had the time. I saw someone on here in PA does a quick replacement for $300. That may be in my future. Do my pictures look typical for a pre-clean condition?
    IMG_0128.jpg
    IMG_0127.jpg
    IMG_0125.jpg
    IMG_0117.jpg
    IMG_0115.jpg
    IMG_0120.jpg


    iPhone ?
     
  5. ASRDogman

    ASRDogman Senior Member

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    The cooler IS the main part to clean. 2nd is the intake manifold......
    The rest is very minor. Getting the cooler out is NOT as hard as some make it sound
     
    Mendel Leisk likes this.
  6. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Auto-exposure renders those pictures not very helpful: you’ve got to increase exposure to see any detail of the passage interiors.

    I’d spring for a new PCV hose; that one looks brittle.