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Help with 4th gen egr installation in 2012 prius

Discussion in 'Prius v Accessories and Modifications' started by Carlos De Castro, Jul 25, 2022.

  1. Carlos De Castro

    Carlos De Castro New Member

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    I am in need of assistance in trying to figure out where the hoses go on the egr. If I could maybe get a diagram as to what the puposes are for each hose? I did get the diagram from the other forum post but I am not understanding it. I just really wish I could find a youtube video that goes into detail of where exactly every hose goes. I'm so close to being done and am ready to hit the road!
     
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  2. Tombukt2

    Tombukt2 Senior Member

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    I thought most were just putting the gen 3 EGR back on the gen4 engine just because of the piping and the fit or something along those lines I'm not convinced the Gen 4 engine solves any problems yet till y'all can make 300k on them or two and some big change we know nothing you got to have enough Gen 4's past the oil burning and oil consumption problem mileage right?
     
  3. ChapmanF

    ChapmanF Senior Member

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    The Gen 4 EGR components are flat out too big to work right, unless you are also switching to the Gen 4 exhaust manifold and catalytic converter.

    The Gen 3 manifold supplies exhaust from before the cat, where the pressure is higher, and that will mean too much EGR through the Gen 4 EGR pieces, which are oversized so they work with the lower-pressure gas from a Gen 4 exhaust.
     
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  4. Carlos De Castro

    Carlos De Castro New Member

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    I thought about doing that, but the egr that came with the prius is so built up with carbon, I can't get it cleaned out... three cans of brake cleaner later and nada. The gen 4 engine was $600 cheaper with only 10K on it...
     
  5. Carlos De Castro

    Carlos De Castro New Member

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    Thanks for the advice
     
  6. bisco

    bisco cookie crumbler

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    you're much better off with the gen4 engine, not just financially. might be worth buying a new or used gen3 egr.
    some have had success cleaning them with a power washer
     
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  7. Carlos De Castro

    Carlos De Castro New Member

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    Have had thoughts about that. Although truthfully, I realized that I already bent the pipe on my third gen exhaust manifold to fit the 4th gen egr... I'm too late to change my mind I think...
     
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  8. Mendel Leisk

    Mendel Leisk Senior Member

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    Try soaks with Oxi-Clean Stain Remover, or Purple Power. May need wire pushed through to get it started. Follow up with pressure washer may be warranted. Bottom line: it CAN be done, be brought back to shiny/new.
     
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  9. rjparker

    rjparker Tu Humilde Sirviente

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    Actually gen4 has big changes. See this post.
    Did 4th Gen fix 3rd Gen? | PriusChat

    What I did was chuck up some stiff wire (maybe it was a wire from a clothes hanger) and drill out each passage. However I did this with the old cooler after the fact; I bought a new cooler at the time.

    Almost every gen4 egr in a gen3 car ends up with recurring codes. So most use the gen3 intake and egr. If you pm me I will point you to a place you can get a cleaned gen3 cooler in San Antonio.
     
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  10. xliderider

    xliderider Senior Member

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    Yeah, brake cleaner doesn't work on the carbon buildup in the EGR cooler.

    You need something a lot more aggressive, oven cleaner, purple power, and my go to, plug one end of the cooler off with a rubber stopper and pour straight heavy duty drain cleaner (NaOH) in and let it soak. Then pour it out, and fill with very hot water, pour it out, repeat rinses many times. As mentioned, for completely clogged coolers, you might need to use a stiff wire to physically push the carbon and oil gunk out of the channels first, so your cleaner can get at the gunk. Repeat process many times, or use a pressure washer if available.

    Posted via the PriusChat mobile app.
     
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  11. Mendel Leisk

    Mendel Leisk Senior Member

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    Aka lye. Our local hardware stores don't seem to have it anymore, just a devil's brew (Draino), comprising some lye, plus various other crystals, and small shards of aluminum. Apparently lye's a meth ingredient. Anyhoo: Amazon still stocks straight lye, a staple in soap making.
     
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  12. ChapmanF

    ChapmanF Senior Member

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    If you're stuck with it, you can look up another thread here where somebody painted himself into the same corner, and ultimately managed to fabricate a restrictor to go in the EGR path to get the flow back down where it needs to be. Might not have been perfect at all speeds and loads, but at least ran mostly decently, didn't suck. You could probably start by imitating whatever size of holes he used.
     
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  13. Mendel Leisk

    Mendel Leisk Senior Member

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    @Carlos De Castro you've bent the exhaust manifold already, to suit the 4th gen cooler flange?

    If not I would persevere with the 3rd gen EGR cleaning.

    If you have bent it, I might just "unbend" it, with copious heat.
     
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  14. Carlos De Castro

    Carlos De Castro New Member

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    I've got confirmation from Hanson 3 years after doing his sway with a 4th gen egr and he says it's running like a champ! So I'm going to continue the journey with the 4th gen egr... thanks for the reply Mendel
     
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  15. Carlos De Castro

    Carlos De Castro New Member

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    Any chance you know where that thread is?
     
  16. Carlos De Castro

    Carlos De Castro New Member

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    Thanks man I might take you up on that
     
  17. ChapmanF

    ChapmanF Senior Member

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    I guess that'd be here.