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Engine coolant and oil loss

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Currahee, Apr 27, 2016.

  1. Currahee

    Currahee Member

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    We have a 2010 Prius with ~120k miles and a supposed oil leak; about half a quart for the last 500 miles. Ongoing for some unknown period of time. I haven't seen any oil on the ground for the past week. Furthermore, the engine coolant is very low. The dealer believes the "seepage" is due to head gasket, which would cost $2400 to repair.

    This isn't my car (my gen 2 runs great), but it reminds me of my beloved 1996 Subaru which had to be let go because of an expensive head gasket and emissions failure. We expected the Toyota engine to last much longer. So far, the Prius hasn't thrown any check engine lights. Is this unusual? Any signs I can look for that might confirm the head gasket leak or suggest a less expensive diagnosis?

    I've included some pictures here:
     
    #1 Currahee, Apr 27, 2016
  2. bisco

    bisco cookie crumbler

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    welcome! actually, it's fairly common. if it's running well and getting good mpg's, just keep an eye on, and top up the oil. there are quite a few threads here if you want to do some research and educate yourself. all the best!(y)

    how are you checking the coolant?
     
    #2 bisco, Apr 27, 2016
  3. working1

    working1 Active Member

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    Was the coolant replaced recently? At 120K it's past due. Just trying to eliminate air being trapped from a coolant change causing the low level.
     
    #3 working1, Apr 27, 2016
  4. Currahee

    Currahee Member

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    Just visually, in the overflow tank.

    AFAIK the coolant wasn't replaced recently, if ever. It looks brighter than my 2007, though, which is also up for a change. I had planned to take in to a trusted non-dealer to change the coolant and get a second opinion on the head gasket. Having just spent over $1000 to replaced the tires and rear brakes, however, we're a bit repair-weary. For the dealer to service all the fluids (coolants, transaxle, brake) would cost over $700.

    Glad to hear it's manageable, so we don't have a catastrophic failure to look forward to in a couple years?
     
    #4 Currahee, Apr 27, 2016
  5. bisco

    bisco cookie crumbler

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    not likely. they say you need to check the coolant in the radiator.
     
    #5 bisco, Apr 27, 2016
  6. Currahee

    Currahee Member

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    OK, I'll do that. Should I bother with oil additives for magical seal conditioning? I noticed there aren't any "high mileage" 0w-20 synthetics.
     
    #6 Currahee, Apr 27, 2016
  7. bisco

    bisco cookie crumbler

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    idk, as i said, there's a lot of discussion in other threads. additives, what weight oil, dino vs syn, etc.
     
    #7 bisco, Apr 27, 2016
  8. JC91006

    JC91006 Senior Member

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    There is nothing wrong with your car's head gasket. The car is just burning oil and you have to keep an eye on it. Top off the oil when needed.

    Prius burning oil is quite common as the miles get higher.....don't let those dealers scare you into giving them money for repairs not needed. You should however get all your coolant changed at 100k miles.
     
    #8 JC91006, Apr 27, 2016
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  9. douglasjre

    douglasjre Senior Member

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    Go to Mobil 1 0W-40 oil. 20 is too thin. It's no wonder the rings are wearing out on these things.
     
    #9 douglasjre, Apr 27, 2016
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  10. zoeboi954

    zoeboi954 Junior Member

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    I am 100 percent certain it is your head gasket. I'm going through the same bull. From coolant lost and burning oil there a chance that you getting air/oil in coolant system which will break your water pump... happen to me. I even tried the liquid that you pour in the coolant to seal the gasket it worked for a while but the problems came back
     
    #10 zoeboi954, Apr 28, 2016
  11. JC91006

    JC91006 Senior Member

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    well your problem is pouring liquid into the coolant.....that's 100% guaranteed to plug up your car's cooling system. It is easy to spot coolant in your oil, just pull out your dipstick and look at it.
     
    #11 JC91006, Apr 28, 2016
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  12. zoeboi954

    zoeboi954 Junior Member

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    I dont agree with using the it, but i poured the liquid in after my pump died and was replaced, my coolant system isn't clogged I'm still getting a flow but I still need to replace the head gasket
     
    #12 zoeboi954, Apr 28, 2016
  13. trip1027

    trip1027 Member

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    Hey I had same issue but it was going into my intake... I just changed the pcv valve and problem was fixed less then $6 for the part. Something to do with the air vacuum but yeah my 2010 had 136000 miles on it when it happened

    SM-N920V ?
     
    #13 trip1027, Apr 28, 2016
  14. Currahee

    Currahee Member

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    OK I'll look into replacing the PCV valve.

    There's no radiator cap on the gen 3 so I couldn't check the level there as recommended above. Doesn't seem to be any residue in the oil (see cap picture) but it's still confusing why the coolant level would be so low if it was just burning oil.

    Most likely we'll stick to the recommended oil since there isn't a consensus on how effective other weights are. If anything it would be sharing high mileage synthetic 5w-30 with the gen 2.
     
    #14 Currahee, Apr 29, 2016
  15. NutzAboutBolts

    NutzAboutBolts Senior Member

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    If you had a head gasket problem, your coolant will seep into the engine oil. To check if that is the problem, you can drain the oil and if it looks murky, then you have a blown head gasket. I wouldn't risk driving your vehicle with a blown head gasket as it can damage your engine as well. Good luck.
     
    #15 NutzAboutBolts, Apr 29, 2016
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  16. Currahee

    Currahee Member

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    I haven't noticed coolant loss since topping off the fluids last month, so if there is seepage it's not serious. The oil burn rate is about 1.5 qt per 3k miles. Bumping this thread to mention that I found a high-mileage 0w-20 offered by Valvoline. This is the only HM oil I can find at that weight, still not sure why. Will use it for topping off from now on.
     
    #16 Currahee, May 25, 2016
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  17. bisco

    bisco cookie crumbler

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    fingers crossed!(y)
     
    #17 bisco, May 25, 2016
  18. working1

    working1 Active Member

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    Assume this is the "Valvoline Full Synthetic with MaxLife Technology". I have found no place to buy this. It appears on their website, but, seems to be vaporware.

    0W-20 Motor Oil 5-Quart Part: 852399 UPC: 0-74130-01578-4
    0W-20 Motor Oil Quart Part: 852400 UPC: 0-74130-01581-4

    Any tips on where to get it would be great.
     
    #18 working1, May 25, 2016
  19. Currahee

    Currahee Member

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    #19 Currahee, May 25, 2016
    Last edited: May 25, 2016
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  20. working1

    working1 Active Member

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    Excellent info. Thanks. Too bad I got enough oil for the next 4 oil changes, but, this will be used after that. I should be at 150K by then.
     
    #20 working1, May 25, 2016
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