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Oil in coolant tank? Blown headgasket possibly?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Priipriii, Mar 12, 2023.

  1. Priipriii

    Priipriii Member

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    Is it possible for engine oil to go inside coolant tank, but not the other way due to a blown headgasket?

    Ive noticed my coolant tank is a dark brown color, but my engine oil is not milky or signs of coolant. I am experiencing misfires as well during idle or low rpm, but none at cold engine start up. No coolant is being lost funnily enough, so i dont think its being burnt, but i think oil might be. Ive also noticed oil marks where the gasket sits when i took off the intake manifold.

    I have not burnt enough oil yet to where it doesnt show up on dipstick. Just slightly lower than when i remember it.

    Will any engine oil seal additives even work on a headgasket? Or will switching to a 0w-25 help?
     
  2. PriusCamper

    PriusCamper Senior Member

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    On Gen 3 the other away around on headgasket failure is rare. But they make a test kit available at auto part stores to determine if you have oil in your coolant and based on symptoms you're gonna wanna replace your coolant regardless of test results. Please keep us updated as this situation is rare and we'd love to learn more.

    One entertaining option is if coolant systems are dealing with exhaust leak outside the engine, which is unlikely, but that would be fun, especially if it was EGR related...
     
  3. Mendel Leisk

    Mendel Leisk Senior Member

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    What's the miles? Every cleaned the EGR components and intake manifold?