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How to clean clogged EGR cooler?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by anonymous, Jul 22, 2018.

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  1. anonymous

    anonymous Member

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    200,000 miles and EGR cooler is completely plugged. Already consumed lots of acetone & carb cleaner but it's not doing much. All I hear about clogged EGR coolers is that they get replaced. Is it even possible to clean it? Or does it have to be replaced? We have a week to either clean or replace the EGR cooler before it has to be smog tested again (failed because of P0401).
     
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  2. ASRDogman

    ASRDogman Senior Member

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    A lot of people use oxyclean, royal purple, carb cleaner, brake cleaner, and let it soak and change every 4 or so hours.
    I used gunk and oven cleaner, as did others, on mine and it worked great.
    Some have used a piano wire to poke through it to clean it out. Just do so carefully.
    If it's fully clogged, it will take time and patience.
    You might be able to check a junk yard for one that's not so clogged so you can clean it up easier and fast
    so you can get it inspected. Then you won't have to rush to get it done.

    Maybe a place that has a glass beader to clean it out.
     
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  3. Raytheeagle

    Raytheeagle Senior Member

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    Pressure washer will help out ;).

    How much oil is your Prius consuming?

    Good luck and keep us posted (y).
     
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  4. anonymous

    anonymous Member

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    so I guess it'll just need to soak for a while, and it'll eventually clear up

    maybe somewhere around 1qt per 1000 miles but i'm not sure.
     
  5. ASRDogman

    ASRDogman Senior Member

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    I also tried a pressure washer that someone said they used. It helped some.
    Soaking seems to be the thing that needs to be done to soften up the hardened oil.
    I sprayed oven cleaner in it and covered the hole until it came out the other end, 4 or 5 times.
    Let it soak for 30 minutes or so then used the pressure washer.
    Make sure you wear some sort of eye protection. I didn't have carb cleaner but brake cleaner helped also.
     
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  6. Raytheeagle

    Raytheeagle Senior Member

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    Maybe, maybe not;).

    You’ll probably have to perform some form of physical act to get the fluids flowing through :(.

    Pressure washer or wire have been tools used in the past and have proven successful :).

    Good luck (y).
     
  7. priusplus_fr

    priusplus_fr Junior Member

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  8. priusplus_fr

    priusplus_fr Junior Member

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    Just a basic question for a beginner: is it possible to clean the EGR cooler /EGR valve without removing any parts?
    Thanks. Any tutorial you would recommend.
     
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  9. Raytheeagle

    Raytheeagle Senior Member

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    The egr cooler is a radiator style device and has many small passages:cool:.

    To thoroughly clean it, removing the cooler is required:(.

    The egr valve you can actuate by removing the black cap (use and impact screwdriver as there are dissimilar materials) and push in the plunger. While this will not clean it, it will free up the valve:).

    I cleaned our 2010’s egr circuit at 120 and 173 k miles and glad I did as the carbon deposits were getting bad:eek:.

    The @NutzAboutBolts videos are a great source for the job. We inspired them to make the videos:).

    Good luck and keep us posted (y).
     
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  10. anonymous

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  11. Mendel Leisk

    Mendel Leisk Senior Member

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    200K miles is a lot, hopefully you can still flow things through. What worked for me, albeit with a lot less miles (around 75K km's):

    1. First tried CRC Brakleen, also running a thin copper wire through. This was somewhat effective.

    2. Then mixed up a solution, using the hottest tap water I could muster, and added powdered Oxi-Clean beyond saturated. Corked the south end, swirled up and poured in the solution.

    3. Let it sit, for maybe an hour, occasionally running the copper wire through. It will bubble up, more and first, then subsiding:

    upload_2018-7-23_13-56-39.png

    The poured out solution:

    upload_2018-7-23_13-57-23.png

    Getting better:

    upload_2018-7-23_13-58-36.png

    4. Pour it out, rinse thoroughly with hot tap water, and repeat, five or six time did it for me:

    upload_2018-7-23_14-0-13.png

    With 200K miles your case will be tougher. There's a couple of similar but maybe stronger products: Purple Power, or maybe Easy-Off Oven Cleaner. You're trying to clean "baked on" carbon, somewhat similar to oven deposits, so something strongly basic is the common denominator of all these.

    Note though, don't use OxiClean or similar with the valve: it has an aluminum body, will react I think. Might be fine, but will really be dulled, and BrakClean will likely be enough.
     
  12. cnc97

    cnc97 Senior Member

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    I soaked my EGR cooler in oxyclean and water for 6 days. Since I was waiting on parts from Toyota it wasn’t an issue. After 6 days I was still getting greasy junk out of it. One hour soaking in Dawn and water and it was clean as a whistle.
     
  13. anonymous

    anonymous Member

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    Oven cleaner seems to help. I've been filling the device with oven cleaner, leaving it for hours, and then flushing it with water…
    We have a pressure washer that someone threw out cause the hose is broken and leaks, but I can shove the input side of the cooler on the pressure washer's output connector. This was very effective the first time, when the cooler was completely plugged; it bursted a couple of veins through. But now that there is some flow it won't hold much pressure to blow any other veins.

    So with the oven cleaner soaking in it, every time i flush I get some color out but it seems to be a very slow process. I think physical force is needed to effectively clear it. I have copper wire that is a good size but it's too malleable to apply much force. I need a very stiff wire/rod of such size (like an extremely long precision screwdriver or nail) but I don't know where to find such a thing (besides online).
    I suppose a strong pressure washer spray would work too, so I should try fixing the hose so it can hold pressure.

    We just passed the smog test without it so I'll be taking my time until the device is completely clean :)

    Does anyone think boiling would work? Boiling it in water with something like dish soap or oxy-clean?
     
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  14. ASRDogman

    ASRDogman Senior Member

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    Dawn soap seems like a good idea. It cleans oil off of birds! :)
    Lowe's is where I bought a kit for my pressure washer. Usually it's the "o" rings that fail. But the cheap plastic
    handle couldn't handle the push from the nozzle and it just bent which caused it to leak.
    I think it was only $30.
     
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  15. anonymous

    anonymous Member

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    So I found an effective way of cleaning the device, using a very straight piece of 12 AWG copper wire and a drill. By spinning the wire with the drill I can slowly wind the wire down each vein without bending the wire. Then just flush the gunk out with water.

    This quickly jumped me from like 10% to 90% complete. The downside of this is that it bends the little teeth inside the veins. Thinner but stiffer wire would be better.

    Unfortunately the wire broke off a few times and I was unable to get all of them out so several veins will have to be left plugged. :oops:

    I drew a diagram to verify that I've checked and cleared all veins, and marked the bad ones with red.
    upload_2018-8-3_22-28-40.png
    It's 93% clear but I think that'll be alright. I should clean it again a lot sooner though.
     

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    #15 anonymous, Aug 4, 2018
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  16. anonymous

    anonymous Member

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    The hose was damaged and had a leak; I fixed it with a 1/4" brass barb coupling and four hose clamps fastened as tight as possible.
     
  17. Raytheeagle

    Raytheeagle Senior Member

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    I plan on doing ours every 50 k miles or so;).

    Basically on te same rotation as the engine coolant. Keep the egr circuit fresh along with the coolant and it should last a good bit:).

    Good luck and keep us posted (y).
     
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  18. royrose

    royrose Senior Member

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    I'm curious how clogged it was the first time around (at 120,000 miles) compared to the second (with an additional 50,000 miles).

    I'm approaching 90,000 miles on mine, car runs perfectly. I'm wondering when I will "have to" do it vs when I "should".
     
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  19. Raytheeagle

    Raytheeagle Senior Member

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    At 120 k miles it was noticeable with deposits, but not completely clogged ;).

    At 173 k miles, a similar condition was found. Our 2010 does consume a quart of oil every 5k miles or so, so that extra carbon going through the system might contribute to that:(.

    Having done this job about a half a dozen times now, while a bit fiddly, it’s manageable as a diy and definitely keeps the system in good sorts :).

    About to do another one (not ours) in a month or so for another members daughter. Another chance to refine the time required (y).
     
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  20. yeldogt

    yeldogt Active Member

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    Mine is at the shop now -- 212k. Intake is off as well -- look nasty. All plugged up except for a portion of #2. It's a dumb design. I did not stay around for the cooler/ ERG separation to check that out ... they are going to soak over weekend. Pulled a plug (done at 152k) and it looked good ... not going to replace again. I have a new OE EGR to install
     
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