Engine Shutter @ 45-50 Mph

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by TwoPriusInTenn, Jun 28, 2025.

  1. TwoPriusInTenn

    TwoPriusInTenn Member

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    Greetings,

    Wife's 2010 with 428,021 miles.

    I replaced the head gasket on this car in 2019. My daughter has had it in Florida. Came down this weekend to change the oil and sparkplugs. I also cleaned the EGR Cooler. (preventative).

    When I was done, I took the car for a drive and it shuttered at 40-50 mph. I checked TechStream and tthere was misfires in Cylinders 2 and 3. Switched around the colis and Techstream is still registering misfire in Cylinder 3,

    I'm thinking the headgasket might be gone again.

    Anything else I should check before throwing in the towel on this?
     
    #1 TwoPriusInTenn, Jun 28, 2025
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  2. Tombukt2

    Tombukt2 Senior Member

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    Nope you pretty much got it we had a persona did this twice . No fun
     
    #2 Tombukt2, Jun 28, 2025
  3. NutzAboutBolts

    NutzAboutBolts Senior Member

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    any coolant leak? That should indicate it.

    Any cold start shutter? How are the fuel injectors? How does the spark plugs look?
     
    #3 NutzAboutBolts, Jun 28, 2025
  4. Grit

    Grit Senior Member

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    Leak down test. If it passes throw parts at it. If it failed, trip down to head gasket replacement again.
     
    #4 Grit, Jun 29, 2025
  5. TwoPriusInTenn

    TwoPriusInTenn Member

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    Yes. Cold start shutter
    Sparkplugs replaced - still shuttering.
    Coolant level is going down in reservoir.

    It's not quite toast yet. But all the signs are there. At 427,000, I think it's telling me it needs to rest.

    Thank you for your input.
     
    #5 TwoPriusInTenn, Jun 30, 2025
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  6. ASRDogman

    ASRDogman Senior Member

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    How many miles on the new head gasket?
    If it's a few hundred, then it's a good bet it could be the head gasket.
    And with that many miles, maybe a remanufactured engine would be best???

     
    #6 ASRDogman, Jun 30, 2025
  7. NutzAboutBolts

    NutzAboutBolts Senior Member

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    It’s possible it’s the headgasket leak again. What brand of headgasket did you use?

    I would pull the spark plugs and put a borescope down the tube and see each cylinder to see if it’s wet. Then check for compression in the cylinder and the coolant reservoir.
     
    #7 NutzAboutBolts, Jun 30, 2025
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