Wrapping stock intake with tinfoil bubble and then heat resistant wrap?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by h1ph0panonymous, Jul 11, 2025 at 3:11 AM.

  1. Brian1954

    Brian1954 Senior Member

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    If you want to lower the engine coolant temperature in your car, the easiest way is to remove the thermostat for the summer and put it back in for winter.

    Lowering the temperature of the air entering the engine will have no effect on coolant temperature.
     
  2. h1ph0panonymous

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    The coolant temp is what will be read to gauge the actual engine temp, there’s no way the coolant temp is going to be 190 in said case if the engine can be cooled, what is heating the coolant?
     
  3. Brian1954

    Brian1954 Senior Member

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    I do not understand what you are writing. All I can say is that the engine will run much cooler if the thermostat is removed. Try removing the thermostat, and you will see the lower engine coolant temperatures that you want.
     
  4. h1ph0panonymous

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    What I’m saying is I use the coolant temp gauge on the scan gauge to give a good guess at the engine temp because I can’t find an x-code that gives me direct engine temp. How is disabling the thermostat sensor going to do anything, the radiator fans will just be running non-stop draining the HV battery causing the engine to RPM higher to invert and charge the battery?
     
  5. Brian1954

    Brian1954 Senior Member

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    Please do what I suggest you do in previous posts. Do a search about the function of a thermostat in an automobile engine cooling system. Hint, a thermostat is not a sensor or electrical device.

    Edit added the following: I did an AI search using Google, which I copied below.

    Warm-up phase:

    When the engine is cold, the thermostat remains closed, preventing coolant from flowing to the radiator. This allows the engine to heat up quickly to its ideal operating temperature.

    Maintaining temperature:

    Once the engine reaches the desired temperature, the thermostat begins to open, allowing coolant to flow to the radiator. The radiator then dissipates excess heat from the coolant, preventing the engine from overheating.

    Continuous adjustment:

    The thermostat continuously adjusts its opening and closing based on the engine's temperature, ensuring a consistent and efficient operating temperature.
     
    #145 Brian1954, Jul 15, 2025 at 11:46 PM
    Last edited: Jul 15, 2025 at 11:59 PM
  6. frodoz737

    frodoz737 Top Wrench

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    I tried being polite. What you are specially proposing will do nothing to help with efficiency or increase the longevity of your Prius engine and stated components.

    Please let us know when/if you ever do it though.
     
    #146 frodoz737, Jul 15, 2025 at 11:58 PM
    Last edited: Jul 16, 2025 at 12:06 AM
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  7. h1ph0panonymous

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    Removing it entirely can lead to overcooling, which forces the engine management system to run at higher revs, increasing fuel consumption and gradually damaging the cylinder head.

    Thanks but no thanks.
     
  8. h1ph0panonymous

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    You have the patience of an alarm clock and the attention span of a toddler.

    I’m looking to reduce heat soak temps at stop light to stop light driving with isolation and wrapping of the engine bay compartments and parts especially closest to the engine.
     
    #148 h1ph0panonymous, Jul 16, 2025 at 12:12 AM
    Last edited: Jul 16, 2025 at 1:30 AM
  9. frodoz737

    frodoz737 Top Wrench

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    Then do something, stop just talking about it...and not listening. I admire thinking outside the box, but you really are chasing a parked car...so to speak.
     
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  10. h1ph0panonymous

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    Don’t tell me what to do old timer, in good time, this was a brain storming thread for me.
     
  11. frodoz737

    frodoz737 Top Wrench

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    :ROFLMAO:...but you won't listen kid. Your car, your call, but that $50 will provide a higher ROI with fluids, filters and routine maintenance.
     
  12. h1ph0panonymous

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    a higher what?
     
  13. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

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    In a car that has no fixed gearing.
     
  14. ASRDogman

    ASRDogman Senior Member

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    OH MY! It's for real! Soak it up! o_Oo_O:barefoot::barefoot::LOL::LOL::ROFLMAO::ROFLMAO:

     
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  15. Brian1954

    Brian1954 Senior Member

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    ROI is an abbreviation for return on investment.
     
  16. Hayslayer

    Hayslayer Member

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    Reading this thread, you are short one important item for that.
    You're talking about doing stuff to your car but don't know what a thermostat is.
    You don't know what ROI is.

    You're more likely to hurt yourself installing the bubble wrap than actually seeing any results from it.

    Anyway, put up or shut up. You've had plenty of opinions and options provided. Get on it and show everyone how wrong they are. Or keep acting like a DB. whatever....
     
  17. Mendel Leisk

    Mendel Leisk MMX GEN III

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    That’s somewhat irrelevant, lol.
     
  18. Brian1954

    Brian1954 Senior Member

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    Yes, the engine will run much cooler after you remove the thermostat.

    So, you want the engine to be about 187F to 188F and not the 190F that you are reading on your scangauge when sitting at a red light. The only way I can think of accomplishing that (without finding a thermostat that is 3F cooler than the standard thermostat) is to turn the heat on inside the car and try different fan speeds. A higher fan speed will reduce the engine temperature more than a slower fan speed. Of course, you will need to have the windows open in the car, and you will have to put up with the higher temperatures while driving the car.

    Out of curiosity, why do you think that 187F to 188F is the best temperature for the engine and not the present 190F.
     
    #158 Brian1954, Jul 16, 2025 at 10:13 AM
    Last edited: Jul 16, 2025 at 10:20 AM
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  19. h1ph0panonymous

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    Because when it sits at 190 at the stop light and I accelerate not even over 2200 RPM or into the PWR area of the bar the Prius shows, it’ll heat up to 193-195 which I absolutely do not understand why or even enjoy seeing it get that high other than the fact it’s heat soaking from a starting point of 190 pre-acceleration. I will add this, I believe it’s been this hot because I don’t have regen braking since I accidentally ripped the rear left ABS wheel speed sensor out when I was hammering out the extremely seized up OEM wheel hub, which I’m going to replace soon. My guess is the engine has been working harder to invert energy to constantly charge the HV battery.
     
    #159 h1ph0panonymous, Jul 16, 2025 at 11:35 AM
    Last edited: Jul 16, 2025 at 1:05 PM
  20. h1ph0panonymous

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    Why would I need to know about the thermostat if the thermostat is not what heats up the coolant.