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Cleaning egr cooler

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Zaza 13, Apr 29, 2020.

  1. Zaza 13

    Zaza 13 Junior Member

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    If it possible to clean egr cooler not to remove it, just to remove valve?
     
  2. hotelprisoner

    hotelprisoner Member

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  3. Mendel Leisk

    Mendel Leisk Senior Member

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    Watch @NutzAboutBolts video if you haven't already, linked in thread pinned at the top of this sub-forum. There's really no way to shortcut the process.
     
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  4. Zaza 13

    Zaza 13 Junior Member

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    I saw close to all videos :)) I paied attention that pipe from cooler goes to exhaust pipe, what could be if this dirt goes there, my cooler isn't stucked. Car started burn oil, not too much close to 1liter on 6-7k kms, my car is on 250k, I thought problem is egr and pcv valve.
     
  5. ASRDogman

    ASRDogman Senior Member

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    Maybe, but you'll blow all the water and solvent down the exhaust to the converter and exhaust.
    Which probably won't be good for them.
    Pretty easy to remove though.

     
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  6. Mendel Leisk

    Mendel Leisk Senior Member

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    upload_2020-4-29_13-5-48.png

    Yeah everything highlighted in yellow in the picture (including passages in the intake manifold) is part of the EGR (Exhaust Gas Recirculation) circuit, and will clog with carbon. The only practical way to clean it is after removal. Here's some info:

    The simplest way to see where you're at, is to check the degree of carbon build up in the EGR pipe, a stainless steel connecting pipe between the EGR valve and intake manifold. Watch @NutzAboutBolts video #16 here:

    Nutz About Bolts Prius Maintenance Videos | PriusChat

    Two or three other videos linked there too, for the full cleaning of the intake manifold, full EGR clean, and Oil Catch Can install.

    Good thread:

    EGR & Intake Manifold Clean Results | PriusChat

    Another:

    Oil Catch Can, Eliminate that knock! | PriusChat

    Some tools worth having:

    E8 Torx socket (mandatory)
    E6 Torx socket (optional, but good to have, to remove the throttle body studs from intake manifold)
    3/8" ratchet wrench, regular and long handle, flex head, you can never have enough (or 1/2 plus reducer)
    1/4" ratchet wrench, or 3/8" to 1/4" reducer
    Ratchet extensions: you can never have enough
    Long needle nose piers, straight and bent tip
    Ratcheting 12mm box wrench (optional, but makes disconnection of the EGR cooler from exhaust easier)
    Torque wrench (3/8" and 1/4" both good to have)
    Floor jack and safety stands (or ramps): basically some method to raise front, if you need to take underpanel off, which you may need to, both for access and to recover dropped items.

    Comment regarding clamping of coolant hose, mentioned and or shown in videos:

    1. When removing the intake manifold for cleaning, you do need to lift the throttle body off the intake manifold. Still, the coolant hoses connected to the throttle body have ample slack, enough that you can leave them connected, and just tie the throttle body to something adjacent, say the inverter wiring harness.

    2. When removing the EGR cooler, removing coolant hoses is necessary, but if you drain 2 liters/quarts from the radiator drain spigot prior (into a clean container), the coolant level in the system will be dropped below the EGR componennts, and you won't spill anything. Just be sure to not tip the cooler when lifting it off (and catch the rear gasket): there are a few tablespoons of coolant trapped at the lower back corner.

    Pour that into your previous drained coolant, and when done pour it back into the reservoir. If you've got the coolant bleed bolt (2010, 2011 model years), leave it open while pouring the coolant back in, till coolant starts coming out. For later model years, leave the topmost coolant hose on EGR disconnected till coolant starts coming out. Also, might help to burp the main radiator hose as you pour the coolant back in.
     
    #6 Mendel Leisk, Apr 29, 2020
    Last edited: Apr 29, 2020
  7. Zaza 13

    Zaza 13 Junior Member

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    Problem is that I dont know how to remove stud bolts, with 2 nuts possible but two studs on back of cooler could be very difficult.
     
  8. Zaza 13

    Zaza 13 Junior Member

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    Hey guys thank u so much, wish u health!!!
     
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  9. Borninblue

    Borninblue Active Member

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    It’s a little rough, but patience and beverages help. Much harder to replace head gasket though. Take it from someone who almost electrocuted himself trying to clean the traction battery terminals (thank God that wire brush handle was wood). If I can get it done so can you.
     
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  10. Raytheeagle

    Raytheeagle Senior Member

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    Save the beverages for the end;).

    Celebrate the accomplishment :).

    Use a pressure washer to clear the cooler(y).
     
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  11. ASRDogman

    ASRDogman Senior Member

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    Wood is a good conductor of electricity.... You were very luck...

     
  12. Borninblue

    Borninblue Active Member

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    Never was the brightest crayon. Interesting why I didn’t feel the shock. I know the combined volts of the entire pack can kill you, but I’m assuming running the brush across a few terminals would have been maybe four or six modules running in parallel would have just knocked me back? Like I said I literally saw a small flame when I ran the brush across. No charge, but underwear change was needed.
     
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  13. Otium

    Otium New Member

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    If I do the entire cleaning, install the oil catch can and keep up on cleaning it, will I still need to go back and clean the EGR cooler and pipe regularly?
     
  14. ASRDogman

    ASRDogman Senior Member

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    Yes! Every 50-75,000 miles.... The clogged cooler is what creates the back pressure causeing the
    headgasket to fail. At least, that is the theory....
    Your driving habits determin how long and how much it cloggs.
    More highway miles seem to cause less blockage.

     
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  15. ChapmanF

    ChapmanF Senior Member

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    Back pressure now? That's another theory!

    I hope somebody's counting how many different theories we have for what the EGR system does to the head gasket.
     
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  16. Tekken

    Tekken Member

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    Doesn't it be around? highway miles drive, use more engine and burn more oil.
     
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  17. ASRDogman

    ASRDogman Senior Member

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    ???
     
  18. 945 PIP

    945 PIP Junior Member

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    I feel like I have joined a sacred crew of those who have gotten the cooler out and reinstalled it. This was a hell of a job!!!! I spent two hours just getting the back nut off and the bottom bolt out. I never want to do that job ever again. Took a total of six hours to complete everything, but the cooler is clean (used a power washer). Was surprised that the cooler wasn't more clogged. Maybe that is due to vast majority of driving on the freeway. No way to know. I did not put the bottom bolt back in as it is totally unnecessary, and I don't think it would have been possible for me to do anyway. Glad it is done!!!!
     
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  19. Mendel Leisk

    Mendel Leisk Senior Member

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    It might be “somewhat” necessary, but I’ll take that risk. Permanently take out the stud from that location out too, and then you can avoid removing the the two rearmost studs. You can do that any time. Go really slow and careful at first; it doesn’t want to break loose, and will resist almost all the way out.
    The second time is not “easy”, but definitely goes smoother. Say in 50k…?
     
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  20. ChapmanF

    ChapmanF Senior Member

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    That's what makes it so important for people doing this job to begin by capturing the EGR flow test result before starting the work, and again after cleaning, and report those (on that thread linked above) with the car's mileage and some other information about the way it's been driven. It's not that there's "no way to know"—there is one, but it's slow, and works better the more people participate.
     
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