1. Attachments are working again! Check out this thread for more details and to report any other bugs.

How to remove the EGR valve/cooler

Discussion in 'Gen 4 Prius Care, Maintenance and Troubleshooting' started by Jdpl76, Aug 3, 2024 at 12:25 PM.

  1. Jdpl76

    Jdpl76 New Member

    Joined:
    Oct 21, 2023
    11
    2
    1
    Location:
    Artesia, California
    Vehicle:
    2016 Prius
    Model:
    IV
    I need to replace the EGR vavle and maybe the cooler.. The problem is that a tutorial I watched is not the same as my year and I don't see any videos of a layout like my 2016 Prius hybrid.

    Directly to the right of the EGR on my car is the inverter which seems to be in the way. Will I need to remove the inverter to replace the EGR vavle?

    Thank you.
     
    #1 Jdpl76, Aug 3, 2024 at 12:25 PM
  2. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    55,667
    38,781
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    What's the miles? Gen 4 EGR systems have proven VERY butlet-proof. @Raytheeagle did his (did require a inverter shift IIRC).. @jerrymildred did one at the shop he worked at, customer request. To best of my recollection in both cases cleaning proved unnecessary; the systems were still very clean.

    Here's Jerry's post:

    Gen 4 EGR cleaning at 360,000 miles | PriusChat
     
    #2 Mendel Leisk, Aug 3, 2024 at 2:15 PM
    Last edited: Aug 3, 2024 at 2:22 PM
  3. Jdpl76

    Jdpl76 New Member

    Joined:
    Oct 21, 2023
    11
    2
    1
    Location:
    Artesia, California
    Vehicle:
    2016 Prius
    Model:
    IV
    150,000. I took a putty knife and blocked the path of the EGR took her for a test drive and the problem immediately went away. No more shaking on acceleration.
     
    #3 Jdpl76, Aug 3, 2024 at 2:58 PM
  4. Jdpl76

    Jdpl76 New Member

    Joined:
    Oct 21, 2023
    11
    2
    1
    Location:
    Artesia, California
    Vehicle:
    2016 Prius
    Model:
    IV
    Also I want to add that I recently changed the oil and may have overfilled the oil then put about 600 miles on the odo. I read somewhere that if we go by the dipstick it is overfilled and to fill it 3/4 below the full mark is a good practice but I filled it to the full line. I already bought the part 04004-58137 for $250 annd this is just for the valve. Before I proceed I just had a few more thoughts and questions.

    Based on what you shared I could be wasting my time and find a squeaky clean EGR valve since the gen 4's really shouldn't have a problem with clogged or sticking EGRs..

    Is is likely that my EGR could have gotten prematurely clogged at 150k because I overfilled the oil recently ?

    Do you believe my diagnosis is conclusive enough to move forward with replacing the EGR valve?

    Do you think I need to replace the cooler also?

    What else could it be based on the test I did and how it ran with a bypassed EGR?

    Thank you
     
    #4 Jdpl76, Aug 3, 2024 at 3:39 PM
    Last edited: Aug 3, 2024 at 3:48 PM
  5. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    55,667
    38,781
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    My hunch is it’s all good. When refilling oil i just put in the specd amount, leave it a few days before checking dipstick. It’s invariably about 3~5 mm below top pip. You’re probably a bit overfilled, but not serious. Gen 3 is a “little” different, but almost the same engine.

    with the EGR, I’d sleep on it. So far very few Gen 4,reports, all saying not to bother; it seems Toyota learned a lot from the Gen 3 beta testers.
     
    #5 Mendel Leisk, Aug 3, 2024 at 6:48 PM
  6. Jdpl76

    Jdpl76 New Member

    Joined:
    Oct 21, 2023
    11
    2
    1
    Location:
    Artesia, California
    Vehicle:
    2016 Prius
    Model:
    IV
    I want to just ignore it but there is another party who does not ignore it if you know what I mean. What do I do about the quick shake on acceleration? It never shakes on idle. It happens at around 15 mph almost ever time. It can also happen at speeds of 50, 70 mph or really any speed when I am trying to just cruise and maintain a speed. If I put into power mode and accelerate aggressively I really don't feel it. It almost feels like a misfire but I have no CEL.
     
    #6 Jdpl76, Aug 3, 2024 at 7:07 PM
    bisco likes this.
  7. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    55,667
    38,781
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Think so.

    You could start by removing the intake manifold, clean it out, and check the condition of the EGR passages. There's a large diameer intake port, and smaller tributaries, one per port. If those small passages are pretty much pristine it'll add weight to the leave it be argument.

    The EGR pipe between EGR valve and intake will likely be easy to do to, check the condition of it's interior.

    Note:

    1. You very likely can lift off the throttle body without removing it's coolant hoses. I wouldn't disconnect those hoses if not needed.
    2. If you do get to EGR cooler removal, and you don't want to do a full coolant drain-and-fill, maybe drain just a couple of quarts (from the radiator drain spigot, into a clean container. This should drop the coolant level below the EGR component, leaving the cooler more-or-less dry.
    3. The top two links in my signature are for third gen EGR cleaning, but may have some relevance. The second link has some ideas on the aforementioned two quart drain.

    Attached are Repair Manual excerpts for intake manifold and egr system. Telling: I just created the EGR excerpt this morning; so far it's never been needed.
     

    Attached Files:

    #7 Mendel Leisk, Aug 4, 2024 at 10:16 AM
    Last edited: Aug 4, 2024 at 1:47 PM
(You must log in or sign up to post here.)