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EGR delete or disabling through software

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

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  1. Tombukt2

    Tombukt2 Senior Member

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    Don't think they'll be any deleting of EGR You might could take control over that electronic EGR valve but what are you going to do with it You've got to be real careful with EGR because it they've planned the given internal combustion temperature shift around the use of the EGR so if you start deleting it that's going to go up to normal non EGR type temperatures you're going to need rings and things that can stand that which I don't think is in the two ZZ FXE but good luck with it.
     
  2. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Yup. But there’s no way around it. When the cars roll out of the factory with clean/functional EGR system, the engine runs as it should, with lower combustion chamber temperatures, all cylinders in balance. Gradually it clogs, and unevenly, till cylinder one in particular is overly hot, then two and so on.

    In the absence of an effective fix from Toyota, it’s what you have to do.
     
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  3. ASRDogman

    ASRDogman Senior Member

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    The engine is burning oil. That's why you have this issue.
    Replace the short block. Or complete remanufactured engine. It "should" have the latest
    pistons and rings to remedy the weak oil rings....
     
  4. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    The Car Care Nut says any new short blocks will have the revised pistons and rings.
     
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  5. Prius Enabler

    Prius Enabler New Member

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    I don’t “know” this but I’ve read the egr only opens when the cylinders are under vacuum, ie engine braking. At least that’s normal operation for most cars I think. Like I said prior this Prius is a whole new beast to me. I could be totally wrong.

    I guess to be more clear on the first part, my thought was to pinch off the exhaust pipe feeding the egr - so no more exhaust.
    Then have the input of the egr cooler open to the atmosphere - filtered of course.
    So when the intake goes into vacuum the egr opens and sucks plain old filtered air into the manifold. Allowing the pistons to freely pump, no vacuum and no engine braking so my generator generates.
    I suppose you wouldn’t really need the cooler at that point.
    So the egr still functions normally, just sucking atmosphere instead of carbon.
    Probably a bogus idea. Just late night pondering.

    And it’s too late for piston rings, I put everything back together last night up to the intake/valve cover/egr, Torqued and sealed. Never noticed blue exhaust though…
     
  6. Prius Enabler

    Prius Enabler New Member

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    Dang. Well. I put it mostly together last night.
    It has new valve springs. And a head gasket kit
    I Didn’t know the rings were that much of a problem. Compression test?
     
  7. Prius Enabler

    Prius Enabler New Member

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    I feel like what you’re really telling me is to fix it up original style and then trade it in for a newer one with a post cat egr.

    Cleaning it while frustrating wouldn’t be the worst thing ever with these type of gaskets but the idea of trying to blast all that build up through the intake valves into the cylinder makes me cringe.
    I suppose you might manually rotate the engine till the valves are closed doing one set at a time…. As I type this I feel like someone is going to say duh thats what we recommended on page so and so.
     
  8. douglasjre

    douglasjre Senior Member

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    Don't waste ur time arguing just block him like I did
     
  9. ChapmanF

    ChapmanF Senior Member

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    Mercy me, after 3+ years I'd forgotten making that post!
     
  10. ChapmanF

    ChapmanF Senior Member

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    Wherever you read that is a source you should probably rely less on.

    EGR is used when the engine is producing power; it mixes the exhaust gas with the incoming air/fuel mixture. Mid-loads are where it is used; the EGR valve closes at low load (otherwise the idle would be rough), and closes at high load (otherwise it would limit the engine's max power).

    At those moderate loads, it does reduce the engine's power a little—which is ok because it matches the moderate load—and is a more efficient way of doing that than having to close the throttle further and pump across it.
     
  11. bbrages

    bbrages Member

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    No EGR at high load is one thing that makes me question the connection between EGR clogging and head gasket failure.
     
  12. ChapmanF

    ChapmanF Senior Member

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    There's been a wider conversation overall about what factors might contribute to head gasket issues. What the clogged-EGR hypothesis seems to have more of than the others is devoted partisans willing to post about it super often, with exaggerated certainty, and leave out the rest.
     
    #112 ChapmanF, Jul 17, 2024
    Last edited: Jul 17, 2024
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  13. Prius Enabler

    Prius Enabler New Member

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    I didn’t believe that “nonsense” about it opening during load until tonight. Drove it around gingerly about 5 miles and the egr did exactly that. During light acceleration it went all the way to 50% perhaps higher I wasn’t recording. That’s crazy to me. Throttling it with its own exhaust.
    Knowing it functions like that makes my fresh air egr idea a lot less feasible. I’m still curious but not that curious.
     
  14. Paladain55

    Paladain55 Active Member

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    Most of the gunk is surprisingly from the Atkinson cycle and how well your rings are currently sealing. If you've been changing your oil every 10k your rings are clogged more and you will have a lot more oil going into the combustion area and intake than someone who changed theirs every 5k. It pukes cylinder air back into the intake manifold at the top of the intake cycle and yup it clogs injectors, coats the inside of the intake ports, the manifold etc...

    Things that help:
    1. change oil every 5000 at maximum with full syn. Most of the sludge is caused by the piston rings getting clogged and it can't control the oil as well anymore so it burns a lot more of it.
    2. Unplugging the egr helps with pinging and detonation, but not with the sludge as much.
    3. You can try a new pcv valve.

    I did the following:
    1. EGR unplugged (no egr anymore)
    2. cleaned injectors, piston rings, intake ports, intake valves
    3. open air catch can crankcase ventilation

    Car consumes ~12oz every 5000 miles, intake ports still get a small coat along with the intake manifold.

    *EGR delete for 3 years now, how time flies.
     
    #114 Paladain55, Jul 18, 2024
    Last edited: Jul 18, 2024