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Post-cat EGR on Gen IV - Carbon fouling like Gen III?

Discussion in 'Gen 4 Prius Main Forum' started by jburg, Sep 17, 2020.

  1. jburg

    jburg Member

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    So after looking into both the 2017+ Camry (A25A-FKS) and 2019+ Corolla (M20A-FKS) I have come to find out that Toyota has incorporated an EGR cooler and valve that is fed with exhaust gases post-cat as is done with the Gen IV Prius. I have never been under the hood of a Gen IV, but it looks like on the Corolla that Toyota seriously redesigned this system (from the Gen III) and the recirculated gases are fed into the cylinder head via an additional manifold plenum that sits in front of the intake manifold. This is most likely to reduce the clogging of the passages noted in the Gen III.

    Question: Has anyone had their GenIV Prius EGR cooler and valve off for a PM? How bad is the carbon fouling? Mileage this was done?

    Thanks!
     
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  2. bisco

    bisco cookie crumbler

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    so far, all is good from what i have read
     
  3. jburg

    jburg Member

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    I found another thread where it was clogged at 70000 miles (n). You were on that thread:

    Gen4 EGR fate? | PriusChat
     
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  4. bisco

    bisco cookie crumbler

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    ouch, you better reconsider then...
     
  5. amos

    amos Active Member

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    my 2016 has 140k on it , so far no maintenance on the egr, no cleaning, not replaced egr valve, not cleaned intake manifold, no oil catch can installed, never checked it but on the alert because of a bad experience with gen 3.
     
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  6. jburg

    jburg Member

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    Any interest in taking off the tube between the EGR valve and the intake manifold to inspect for carbon buildup?
     
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  7. bisco

    bisco cookie crumbler

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    if you've never checked it, how can you be on the alert? a visual or audible problem could be too late
     
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  8. amos

    amos Active Member

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    I THINK I IWLL DO A COMPLETE CLEANING OF THIS WHOLE PATH WHEN CAR GETS TO 150K. right now its too hot for anything
     
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  9. bisco

    bisco cookie crumbler

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    i'll try to blow some of our frigid air out your way :)
     
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