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Cylinder 3 misfire please HELP

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Kristopher Moats, Jan 26, 2023.

  1. Kristopher Moats

    Kristopher Moats New Member

    Joined:
    Jan 26, 2023
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    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    V
    Driving home the other day I noticed a shutter on acceleration. Checked the codes and had a cyl 3 misfire. I replaced the head gasket last year. Came home swapped the plug and coil pack to a different cylinder and still had #3 misfire, cleaned the intake and egr tube and cooler still #3 miss, swapped the injectors and still #3 miss, I have 150+ psi compression in all cylinders, used a noid light to verify that injector is getting a power signal, its is! No coolant consumption it does burn oil but it's a 3rd gen so that's expected. If I disconnect the coil while it's running the engine smooths out some also smooths out while the engine is running at a higher rpm. At idle it shakes you to death. I'm lost HELP.
     
  2. tankyuong

    tankyuong Senior Member

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    Location:
    Central MO
    Vehicle:
    2012 Prius c
    Model:
    II
    try leak down test
     
  3. Tombukt2

    Tombukt2 Senior Member

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    Nov 29, 2020
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    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    If you pull the number 3 plug what is the coil look like Is it got red dust on it do all the coils look the same? Pull the plug out of the number three cylinder do you see little micro water droplets on the part that's sitting inside of the combustion chamber below the threads? Smell it move away from the car do you smell coolant on the tip of that plug If so there you go there is coolant getting in that cylinder somehow and generally it's the head gasket that seals that up all the way across all four or you're missing a piece of metal along that seal surface around number 3 whichever it has to be pulled apart to be looked at You can run leak down tests and stick borescopes down there to your old. Really might not ever see a thing A well done leak down test should give you the colors you're looking to see You may have to do it twice.
     
  4. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
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    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    What was the miles for:

    1. Head gasket replacement
    2. EGR cleaning
    3. Current
     
  5. tankyuong

    tankyuong Senior Member

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    Vehicle:
    2012 Prius c
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    II
    i say if head gasket not done right it will blow prematurely
     
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