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. h1ph0panonymous

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    Did you at least remove your all-year-round grill block insulation from the sides of under the bonnet like I recommended?
     
  2. ChapmanF

    ChapmanF Senior Member

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    Ah, perfect. You've got a link, right?
     
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  3. frodoz737

    frodoz737 Top Wrench

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    Your project, your call. You're not done yet?
    As to you next post...I do this for a living and because I love what I do. All we are hearing from you is talk.
     
  4. Brian1954

    Brian1954 Senior Member

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    Well I learned something today. This morning I hooked up Techstream to my 2011 Prius which has the latest ECM firmware. The car had been sitting all night so the coolant temperature was 81F and the ambient temperature was the same. I started the car and watched the coolant temperature and engine water pump speed. As soon as the engine started, the water pump turned on to about 2600 rpm. When the coolant temperature got to 104F, the engine shut down and the water pump continued running for ~13 seconds and then shut off. I would like to note that the heat and fan were tuned off. This was exactly like rjparker described.

    I used the car to run an errand and came home. I connected Techstream again to see how the water pump behaved when the coolant was between 185F and 190F while sitting in my driveway. The water pump behaved the same at those coolant temperatures. I could not get the engine coolant higher then 190F while sitting in my driveway. When the engine was not running and the water pump was off, I then turned the heat to maximum (HI) and turned on the fan. As soon as the fan turned on, the water pump also turned on. When I turning the fan off, the water pump immediately turned off.

    This may have been common knowledge by some in this forum, but it is new information to me. I have been reading the Gen 3 forum for the last 5 years and do not remember see this previously. I should note that my memory is getting worse as I age, just like most people.

    Thank you rjparker for the information about the engine water pump behavior. This thread has now become more then entertainment for me. It has also become informative.
     
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  5. h1ph0panonymous

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  6. frodoz737

    frodoz737 Top Wrench

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    Shouldn't you be turning wrenches?
     
  7. h1ph0panonymous

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    Haven’t bought the material yet.
     
  8. rjparker

    rjparker Tu Humilde Sirviente

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    My v water pump shuts off immediately with the engine until full warmup. Then the short delay. I am sure it helps mpg but is likely to cause cylinder hot soaking. It's something I noticed maybe ten years ago when I observed significant thermal cycling of the engine when not moving but still in Ready.


    Using throttle to run engine in Ready

    Which was the reason to start realtime coolant monitoring with a 210f alarm.

    Prius P10 temp 8.jpeg

    No tin foil but frequent coolant changes.
     
    #108 rjparker, Jul 12, 2025 at 2:23 PM
    Last edited: Jul 12, 2025 at 2:31 PM
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  9. ChapmanF

    ChapmanF Senior Member

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    Great, thanks for linking to a thread I'm sort of familiar with.

    Can you be specific about what in that thread you are basing "1800-2200 RPM is it’s sweet spot. Just enough intake suction to keep it at 188 degrees" on?
     
  10. h1ph0panonymous

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    Based on the posters exact experience that matches mine.

    This post that we are in right now is about how to get that 188 to 186 or 184 degrees during 1800-2200 RPM driving methods. (Babying it)

    My idea is to wrap intake and other areas with an insulating material (tinfoil/aluminum bubble wrap) and then gold wrap over that to create an insulating and isolating barrier between the radiating thermal energy from engine. One could say well all of that is still trapped inside the engine bay so its black body radiation will equalize the whole and all of its parts of the engine bay to the same temperature but the intake isn’t generating heat itself, when the air it picks up is cooler than the engine, the insulating material will start to cool down creating a mini cold soak of the intake.
     
  11. ChapmanF

    ChapmanF Senior Member

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    Which poster? This shouldn't be hard. Asked for a link, you linked to a thread. So the post you're talking about ought to be somewhere in that thread, right?
     
  12. h1ph0panonymous

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    The person who posted it LOL all you have to say after that?
     
  13. frodoz737

    frodoz737 Top Wrench

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    So...this day is just about over now. Are you done with the mod yet?
     
  14. ChapmanF

    ChapmanF Senior Member

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    Can somebody else take a look? h1ph0panonymous made this claim:

    and was asked just where "in these forums" that was "brought up", and replied by linking this thread:

    That's a short, one-page thread, 19 posts, so I read it through and asked h1ph0panonymous to identify any post in that thread that could be the origin of that claim.

    That's produced neat non-response responses from h1ph0panonymous like "Based on the posters exact experience that matches mine." and "The person who posted it LOL"—all without locating any such post.

    Anybody else see such a post there that I'm somehow missing?
     
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  15. h1ph0panonymous

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    The “poster” means the person who posted the post. Do you not see his inquiry based on his Gen 2 driving methods? Even the graphs you commented with are not much different than the Gen 2.
     
  16. ChapmanF

    ChapmanF Senior Member

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    Please either:

    (1) identify the post that supports your claim (each post on PriusChat is directly linkable, this is easy), or

    (2) wait for someone else to see whether I have missed such a post, or whether I'm right that you're blowing smoke.
     
  17. Brian1954

    Brian1954 Senior Member

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    Yes, the person who made the post. Or just tell us what the post number is. The thread starts with post #1 and increments up to the last post, which is post #19. Just say what the post number is that you are referring to.
     
  18. Brian1954

    Brian1954 Senior Member

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    I will answer this for the OP.