1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Loosing anti freeze

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Dominic&Leslie, Jan 2, 2021.

  1. Dominic&Leslie

    Dominic&Leslie Junior Member

    Joined:
    May 31, 2014
    19
    4
    0
    Vehicle:
    2012 Prius
    Model:
    Four
    2012 prius w/240k miles.
    Im losing anti freeze and when its very low, i loose my heat too, i assume thats to be expected.
    In addition, when i do run the heater, this serms to be the only time I loose anti freeze. Turn the heater off and all is fine. In fact I took a 10 hour trip in it the other day with no problems, i just didnt use the heater.
    Also, when i do run the heater, there seems to be smoke coming from the center, left side (drivers side) of the engine compartment, as you are sitting in the drivers seat.
    Any advice you can offer would be great.
    Thank you !!!
     
  2. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    5,834
    3,136
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    Sounds like you have a leaking heater core.
    But, I do not think there is heater valve. There's just a flap the redirects the air around the heater core.
    You need to do a pressure test and see/hear where it's leaking.

     
    Pluggo likes this.
  3. Pluggo

    Pluggo Senior Member

    Joined:
    May 23, 2016
    608
    532
    0
    Location:
    Folsom, Pennsylvania
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Advanced
    The smoke/steam you are seeing is a useful indicator. Bring the engine up to normal temperature, park in your driveway, turn on the heat, and check everywhere for drips with a flashlight. With any luck, you'll see something you can fix. You did not mention smelling coolant in the passenger compartment, so that's a hopeful sign that a leaky heater core may not be the problem.
     
  4. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,464
    38,101
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Just curious, doubly so with 240K miles: have you ever cleaned the Exhaust Gas Recirculation circuit and Intake Manifold.
     
  5. Dominic&Leslie

    Dominic&Leslie Junior Member

    Joined:
    May 31, 2014
    19
    4
    0
    Vehicle:
    2012 Prius
    Model:
    Four
    Hello Mendel Leisk,
    Im older and at times forgetful but seems to me someone else recently mentioned the egr valve to me too. To answer your question, I've yet to touch the egr valve.

    Honestly we live on a fixed income and absolutely love our prius. We have made it to 240k miles performing a minumum of maintenance. Aside from oil changes, tires and brakes, we havent done anything to the car. Wait thats not totally true, we did do the spark plugs, boots and a clock spring to fix a broken horn, at about 220k miles.
    About a month ago I had the dreaded check hybrid system light come on. At about the same time that happened we had an odd electrical problem occur. When you turned the car off, the outside driving lights would turn off too, as expected, what wasnt expected was after about 3 to 5 minutes later, after turning the car off, the back lights, and only the back lights would turn back on. Not the headlights, only the back lights. Well out of pure fear of draining the cars battery and becoming stranded, I would disconnect the cars battery whenever I parked it to prevent draining the battery. This not only worked like a charm as a temporary fix but the dreaded "check hybrid system" light never came back on, and well the back lights stopped misbehaving and are now operating correctly and I dont disconnect the battery anymore.
    Talk about Toyota quality, I just love a car that fixes its own problems itself without my having to hire a mechanic.

    I am preparing to locate a mechanic that i can trust with my prius. The last one who did our plugs was a rip off in my opinion, he charged us 300 to do the plugs, and i supplied the plugs, plus he charged me an xtra hundred bucks to replace the 4 boots on the spark plugs, which i thought was really price gouging considering i can buy the boots for about 5 bucks a piece.

    Im thinking maybe my hybrid battery may be getting weak, which in turn caused the odd electrical problem I experienced. Of course Im just guessing at this point. I do know I have to fix the exhaust gasket to pass inspection and to get the check engine light off. A mechanic explained to me that the egr is after the exhaust leak, which means the check engine light is pointing to the exhaust leak not the egr valve, but maybe he has it backwards? What do you think? (Sorry for the long reply)

     
    Mendel Leisk likes this.
  6. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,464
    38,101
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I’ll give more info later, but one thing: you’re way overdue for Exhaust Gas Recirculation and intake manifold cleaning. Best done by 100k. Owners are blowing engines due to this. And Toyota doesn’t want to know.
     
    mjoo and Grit like this.
  7. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,103
    4,032
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    That’s insane to think that!!!
     
    Mendel Leisk likes this.
  8. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,464
    38,101
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    @Dominic&Leslie again, with 240k it’s likely the coolant loss is due to head gasket failing, so Exhaust Gas Recirculation cleaning too late, though still good to do. A leak-down test can confirm head gasket condition. Anyway, here’s info on dealing with the Exhaust Gas Recirculation:

    Link
     
    Grit likes this.
  9. Dominic&Leslie

    Dominic&Leslie Junior Member

    Joined:
    May 31, 2014
    19
    4
    0
    Vehicle:
    2012 Prius
    Model:
    Four
    If it was the head gasket wouldn’t I have antifreeze in my oil?
     
  10. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,464
    38,101
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Coolant often leaks into the combustion chamber

    Addendum:

    Then there’s a danger of hydro lock. .
     
    #10 Mendel Leisk, Jan 15, 2021
    Last edited: Jan 15, 2021
    Grit likes this.