EGR delete or disabling through software

Discussion in 'Gen 3 Prius Main Forum' started by Juntuner, Apr 30, 2021.

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  1. heltonsc

    heltonsc Junior Member

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  2. ASRDogman

    ASRDogman Senior Member

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    Welllllll.... it's nice to know that in Prius Chat we are not intelligent enough to discuss anything that is
    complicated or expensive...
    Please excuse me while I tie a fresh carrot to the string in from of my donkey, I need to take him to
    get new shoes.... I don't know why, it's too complicated to discuss, I was just told to get it done. :(:cry:
     
  3. frodoz737

    frodoz737 Top Wrench

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    Yep...this is Priuschat. :rolleyes:
     
  4. PriusII&C

    PriusII&C Member

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  5. Mendel Leisk

    Mendel Leisk Senior Member

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    I wonder what Toyota does in Brazil, in absence of EGR? Maybe different cam shaft lobes, varied timing?
     
  6. ChapmanF

    ChapmanF Senior Member

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    Nothing wrong with that, and it probably means that on some subjects you know what you're talking about.

    This could be one of them, if you'd make a small effort to learn.

    It's sometimes said the real test of how well you know something is in whether you can explain it. When the time comes that you can give an explanation of what "enrichment mode" is and why eliminating that helps MPG (pretty simple really), and can explain what the differences are between diesel and SI gasoline engines that matter to the effect of EGR, then you'll be getting up to speed.

    Until then, you're blowing smoke.

    Great! The same journals that published the experimental results cited back in #12 for the 5 to 30 % MPG improvements will still be accepting submissions when you've shown what was wrong in those results.
     
  7. frodoz737

    frodoz737 Top Wrench

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    I can always count on PC when I want a good laugh.
     
  8. fuzzy1

    fuzzy1 Senior Member

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    Here is another voice on efficiency improvement via EGR:

    Exhaust gas recirculation - Wikipedia

    "... Another primary benefit of external EGR valves on a spark ignition engine is an increase in efficiency, as charge dilution allows a larger throttle position and reduces associated pumping losses."

    "... The impact of EGR on engine efficiency largely depends on the specific engine design, and sometimes leads to a compromise between efficiency and NOx emissions. A properly operating EGR can theoretically increase the efficiency of gasoline engines via several mechanisms:

    • Reduced throttling losses. The addition of inert exhaust gas into the intake system means that for a given power output, the throttle plate must be opened further, resulting in increased inlet manifold pressure and reduced throttling losses.[6]
    • Reduced heat rejection. Lowered peak combustion temperatures not only reduces NO
      x formation, it also reduces the loss of thermal energy to combustion chamber surfaces, leaving more available for conversion to mechanical work during the expansion stroke.
    • Reduced chemical dissociation. The lower peak temperatures result in more of the released energy remaining as sensible energy near Top Dead Center (TDC), rather than being bound up (early in the expansion stroke) in the dissociation of combustion products. This effect is minor compared to the first two.

    EGR is typically not employed at high loads because it would reduce peak power output. This is because it reduces the intake charge density. EGR is also omitted at idle (low-speed, zero load) because it would cause unstable combustion, resulting in rough idle."
     
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  9. Mendel Leisk

    Mendel Leisk Senior Member

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    I understood some of the words in that. :oops:
     
  10. wheezyglider

    wheezyglider Active Member

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    Well that middle point is interesting because it says the cylinder will heat up more without EGR. Wonder what happens to the head gasket when some cylinders are consistently heating up more than others.

    I realize Occam's razor -- "the simplest explanation (with some evidence) is the best" -- may have already given us a more likely explanation for possible head gasket failures due to EGR issues, but I don't want to lose track of other possibilities. (And ok I'm stirring the pot just a little while I'm waiting for the wife to get ready to go out...)
     
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  11. heltonsc

    heltonsc Junior Member

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    I do not know how to tell you ... One more fact that there is not even a case of a blown head gasket here.
     
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  12. ChapmanF

    ChapmanF Senior Member

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    Where does one find those statistics?
     
  13. heltonsc

    heltonsc Junior Member

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    only 750 gen 3 units were sold in Brazil, in our internet forums and telegran / whatsaap groups I have never seen any cases of blown gaskets.
    but defects in the abs actuator are very common, very expensive repair!
     
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  14. AW82

    AW82 Member

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    What they do for what? To reduce emissions? To improve mpg? If your question is what do they do to keep the lack of EGR gas from damaging the engine, then I'd presume the ECM adjusts timing, fuel trims, etc just like it does on North American models when the EGR is uniformly not flowing.
     
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  15. ASRDogman

    ASRDogman Senior Member

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    Perhaps the exhaust gases just go out the exhaust?
     
  16. Grit

    Grit Senior Member

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    Greta will not be happy to hear that
     
  17. Grit

    Grit Senior Member

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    cite your sources
     
  18. ASRDogman

    ASRDogman Senior Member

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    Welllllllllllll blesssss herrrr hearttttt
     
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  19. Grit

    Grit Senior Member

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    :ROFLMAO:
     
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