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2010, 110k miles, low oil and engine coolant, thoughts?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by mtnbkr, Sep 7, 2017.

  1. mtnbkr

    mtnbkr Junior Member

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    I have a 2010 with 110k. It's been running great and only needing oil changes so far. I've done the trans fluid a few times as well. No significant oil usage noticed until recently.

    At the last oil change, I only had about 1qt left. I also had the engine coolant about 1" below the low time. I changed my oil like normal and went ahead and drain/filled the engine coolant.

    No odd driving behavior and no obvious contamination in the used oil and coolant looked new. At this point I was just planning to monitor levels more carefully. Should I do anything else or check anything else?
     
  2. tankyuong

    tankyuong Senior Member

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    use 5w30 oil next tome and clean your egr before you blow a headgasket
     
  3. bisco

    bisco cookie crumbler

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    unfortunately, if you don't check your oil between changes, there's no way to know if you have a problem, or they didn't fill the oil properly last time.

    as for coolant, you need to pull the shroud off the radiator, and look into the radiator when cold to see if there is any coolant.
     
  4. mtnbkr

    mtnbkr Junior Member

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    I guess I've gotten lazy between OCIs. I changed the oil myself so I know what I filled it to. It was full and properly filled. I always use the factory filter and mobil 1 0w20 synthetic since new.

    So how does one accurately measure the oil? Sure I check the dip stick but are people taking measurements between the dots or what? I don't know how to realistically gauge it. I know this last time I was careful to fill it to just below the top dot. I've always taken my measurements after the car has been warmed and off for about 10 minutes. I don't know if that's what I should be.

    I just drained and filled the engine coolant via the posted vids. Does pulling the shroud and looking give me any more information at this point?
     
  5. bisco

    bisco cookie crumbler

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    there are posts here about how much oil is between the dots. i'm not sure, but it might be in the o/m. i think checking it in the morning, cold, is the best.
    and there are many threads about 2010 engine issues including oil burning, clogged egr's and head gaskets blowing. you should do some research.

    filling the reservoir doesn't always fill the radiator. you really need to make sure the radiator is filled, then top up the reservoir. there are threads about this too.
     
  6. Mendel Leisk

    Mendel Leisk Senior Member

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    There's no radiator cap on third gen. Yeah, I was incredulous, looked and looked.
     
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  7. NutzAboutBolts

    NutzAboutBolts Senior Member

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    The only way to fill the engine coolant is through the reservoir because the pressure cap is on there and not on the radiator :(

    I feel you might have a blown head gasket... if you're losing oil and coolant, it's leaking somewhere...
     
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  8. mtnbkr

    mtnbkr Junior Member

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    I'm an extreme novice for car repair so please be patient. Should I have seen contamination in the oil then? It looked pretty normal and no milky appearance, which I think is what I'm supposed to look for.

    Anything else I can check? Ive never added fluid to the coolant before. It could have been low for a while.

     
    #8 mtnbkr, Sep 9, 2017
    Last edited: Sep 9, 2017
  9. NutzAboutBolts

    NutzAboutBolts Senior Member

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    Maybe remove the plastic under panel and check for leaks?
     
  10. tankyuong

    tankyuong Senior Member

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    i would get a cheap endoscope on ebay and check inside each cylinder
     
  11. Robert Holt

    Robert Holt Senior Member

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    In my unfortunate experience with blown head gaskets on other cares, the symptoms depended on exactly WHERE the blown head gasket was leaking into: if a section between the coolant tube and an oil tube gave way, the coolant would end up in the oil and give that foamy milky color, but if the section between the coolant tube and the combustion chamber gives way, however, the coolant enters the combustion chamber directly and is consumed, resulting in a fluffy whitish ash on the spark plug electrode, but no oil contamination. (IIRC , I also experienced repeated coolant overheating when the head gasket failed this way, not sure.) Hope this helps
     
  12. mtnbkr

    mtnbkr Junior Member

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    I can pull the plugs to look and I guess if I do that mighty as well replace it? Is that worthwhile? Do I need to change anything else while I do the spark plugs?