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Engine thermostat

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by ThePackage, Dec 20, 2009.

  1. ThePackage

    ThePackage New Member

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    I have read alot of discussion concerning blocking the grill in the winter. I tried that in my '06 with limited success. I monitor water temp using my scangage. During the summer, here in the NE, the water temp stabilizes quickly between 180-190. Now that the winter is here with temps in the 10's & 20's, my engine water temp barely goes above 150. Has anyone had similar experiences and is changing the thermostat the probable solution?
     
    #1 ThePackage, Dec 20, 2009
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  2. ken1784

    ken1784 SuperMID designer

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    It is normal behavior in cold situation, especially on non highway driving.
    The thermostat starts to open at 82C(180F) and it becomes fully open at 95C(203C). We see approx 88C(190F) on normal condition after warming up.
    In cold weather, the cabin heater steals the heat from ICE, therefore you won't see above 180F, especially on below 42mph driving (sometimes ICE stops).

    Please try to turn off your climate control on highway driving once in a while.
    The ICE always runs, then you'll see above 180F if your thermostat works correctly.
    Maybe, you have to bear on cold cabin for a while. :)

    Ken@Japan
     
    #2 ken1784, Dec 20, 2009
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  3. 2009Prius

    2009Prius A Wimpy DIYer

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    Yes I have a ScanGauge II and the ICE coolant T drops steadily at 0 RPM with the cabin T set at 65 F and fan at lowest. If I turn the fan off then the coolant T stays constant. Very dramatic difference even the lowest heat and fan would make.
     
    #3 2009Prius, Dec 20, 2009
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