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[Solved] Engine Coolant Temperature Sensor location?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Digestion_08, Sep 10, 2016.

  1. Digestion_08

    Digestion_08 New Member

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    Hi all,

    Could someone help me locate the ECT sensor for a 2011 Prius so I can replace it ?

    Thank you.
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    I believe it's this:

    upload_2016-9-10_19-16-32.png

    I've attached a Repair Manual excerpt on removal/install:
     
  3. Rebound

    Rebound Senior Member

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    19mm union nut wrench. I'm sure everyone's got one of those lying around...
     
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  4. Raytheeagle

    Raytheeagle Senior Member

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    While everyone may not have one, a set of flare nut wrenches can be bought at harbor freight relatively cheaply ;). And it goes up to 22 mm so you're covered.
     
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    When I google "union nut wrench" I get all these hits for "flare nut wrench", which is essentially a box wrench with a smaller than open wrench opening, giving you two more corners, compared to an open ended wrench.

    Actually I don't see why a box wrench wouldn't work, you've removed the connected line first. Or a deep socket.

    I keep trying to justify getting one of these:

    image.jpeg

    I'm not sure, you might need to remove the wipers, their motors and the cowl (per @NutzAboutBolts video on spark plugs), but hopefully uneccessary.
     
  6. Rebound

    Rebound Senior Member

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    Oh, snap! Another excuse to buy more tools!
     
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  7. Raytheeagle

    Raytheeagle Senior Member

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    As if you needed an excuse to buy another tool:rolleyes:.

    I guess if @Mendel Leisk keeps supplying the repair manual, we'll find other tool needs:).

    I know my small garage is getting full, but always room for one more(y).
     
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  8. Rebound

    Rebound Senior Member

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    My rolling chest is taller than me, and it's packed! I never thought I'd fill it back when I bought it.
     
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  9. Digestion_08

    Digestion_08 New Member

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    Wow, thanks. You rock.
     
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  10. Shahzad Nayyar

    Shahzad Nayyar Junior Member

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    Ok... reviving an old thread.... when u remove that ect sensor, does the coolant immediately come out? Is it kind of like, DIPPED in coolant. I removed my ECT but coolant did not come out. Rather it was after reving up for some 10 seconds that the coolant came out... Does that mean theres air in the system?

    Posted via the PriusChat mobile app.
     
  11. Mendel Leisk

    Mendel Leisk Senior Member

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    This is the component directly above the Exhaust Gas Recirc Cooler, sort of a T-connection with hoses leading in and out?

    In 2010~2011 model year, that component had a white cap you could unscrew for bleeding air. So I'd say yeah, that's the high point, and where air would likely connect. I would try to put it back together while coolant is flowing out.
     
  12. Shahzad Nayyar

    Shahzad Nayyar Junior Member

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    Thanks for the prompt reply. I would do this tonight and get back to you. I was also thinking that initially the coolant came out but i put the sensor back once the coolant stopped coming out. What if the system had sucked in air

    Posted via the PriusChat mobile app.
     
  13. Mendel Leisk

    Mendel Leisk Senior Member

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    Not sure, but my hunch:

    The system is more likely to be pressurized than sucking, and that component is at the high point, so air collects there, as the coolant level rises (during refill). I think you've got rid of at least some of the air that was in there, improved things.
     
  14. Shahzad Nayyar

    Shahzad Nayyar Junior Member

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    Ok one suggestion..... shud i fill the circuit from the area where the ect is removed from. U know, fill the circuit from the highest point

    Posted via the PriusChat mobile app.
     
  15. AzusaPrius

    AzusaPrius Senior Member

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    No leave that open and fill from the coolant tank until it comes out of the highest point.
     
  16. Mendel Leisk

    Mendel Leisk Senior Member

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    I purposely drained some coolant when doing EGR cooler cleaning (to avoid spillage). My 2010 has the vent there, which I opened when pouring coolant back in at the reservoir, and as I did the pouring I could feel air rushing out at the vent.
     
  17. Shahzad Nayyar

    Shahzad Nayyar Junior Member

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    With the car off or in READY?

    Posted via the PriusChat mobile app.
     
  18. Mendel Leisk

    Mendel Leisk Senior Member

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  19. AzusaPrius

    AzusaPrius Senior Member

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    You want to turn the heater on all the way up full blast have the car running as you are filling it up, it would be best to put the car into maintenance mode.
     
  20. Shahzad Nayyar

    Shahzad Nayyar Junior Member

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    Mendel Leisk likes this.