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EGR & Intake Manifold Clean Results

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Rebound, Jun 25, 2017.

  1. Bay Stater

    Bay Stater Senior Member

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    When I did the EGR cleaning two years ago, I lost the gasket underneath the frame work in this concern. I improvised making one from an exhaust manifold gasket sheet purchased from a local auto parts store like this.
    IMG_20180311_160101238.jpg


     
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  2. Rebound

    Rebound Senior Member

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    I wouldn’t replace the MAF sensor yet.
    First clean it with MAF sensor cleaner and make sure you reconnected it.

    Second, those codes DO NOT tell you which part has failed. Your engine computer configured itself to compensate for the blocked EGR. When you started the engine, the compensated values were causing the fuel trim to be very wrong. That’s why you needed some time.

    It may be a bad MAF sensor, but if you didn’t have the CEL light before you did the work, then I doubt it’s your problem. Just check the MAF connection and keep driving the car.
     
  3. Scarface2005

    Scarface2005 Member

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    So I’ve spent all day reading the threads and working on my 2012 plug in with 248k miles.

    my symptoms were the dreaded shakes

    I’ve never cleaned the egr cooler or intake manifold

    I change the oil every 5k, clean the throttle plate every 10k, change transmission fluid every 60k, and finally put new plugs in at 230k, they were in good shape, no pics, only slightly ‘calcified’.

    I maintained an 05 Prius for 295k miles; new battery at 200k/12 years, new 3 way coolant valve at 220k, new cylinder 1 spark plug every 10k after I hit 250k.

    so I had no idea the turd generation needed the egr cleaning so often.

    I don’t wanna spend too much $$ or time chasing around the egr and intake manifold cleaning if I have a bad head gasket.

    I am testing the heat in the cabin right now. It works great, thank god. But, I have noticed some coolant loss. Anyone suggest any easy way to check definitively if it’s the head gasket?

    I have a new PCV valve and air intake manifold gasket. Anyone wanna help me out? I’m at beautiful Lake Gregory in Crestline, CA at 5500’. It’s in the 70’s. Bring friends and I’ll set them up on my kayak at the lake. Or, I can come to you.
     
  4. FriedCells

    FriedCells Member

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    I would second this. I just did the EGR/intake/throttle cleaning myself about 2 weeks ago for the first time. On my 2011 with about 150,000 miles. Did Oxi-clean about 15x on 1 hour soaks and flushes. Then took it to a car wash for the pressure wash. The Oxi did well, but that pressure washer really did in a few minutes what might have taken a couple more days for Oxi to achieve. Mine was severely clogged. Sorry for bad photo:
    IMG_20200709_170116.jpg
    Nothing could pass through there. After pressure wash, could see light though all the holes. Anyways, after about 400 miles after cleaning, I got a P0101 code (MAF sensor). I have my own OBD scanner, so was easy to check. I left it on in hopes that it would go off by itself after some time. Also, I was surprised that my mpg's went down to 44mpg no matter how hard I tried to get it higher when before the cleaning, I was at 47-48mpg's pretty easily. Code wouldn't go off after another 500 miles. After 1000 miles, my mpg's were still at 44. I then erased the code, reset my trip counters and started on my 3rd tank since the cleaning. Finally, mpg's are back to 47-48 (but kinda surprised that there is no improvement after the cleaning as I really cleaned out a lot of gunk from the cooler that was totally clogged and now like new, the EGR pipe was like new when I was done, the hose from the PCV (also changed) to intake was full of dry gunk that I cleaned out, intake manifold had oil all over the place and gunk in all it's holes that I cleaned out, cleaned MAF sensor with MAF sensor spray, changed transmission fluid and coolant reservoirs, and added oil catch can). I really expected to see an improvement in mpg's. But I digress, now halfway through 4th tank of gas (so about 750 miles since deleting MAF code), and the code has not returned and mpg's stable around 48. So it seems that it took about 1000-1,500 miles for the computer to relearn the mpg's and not throw a code.
     
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  5. trojandnc

    trojandnc New Member

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    Thanks for the reply. I had them change the MAF last week and took out the EGR cooler again last weekend. No more CEL and have the old MAF sensor.

    Once I replace the rear EGR gasket to see if that resolves the exhaust noise (the gasket was cracked when I put it back in) and clean the intake manifold/throttle body this weekend, if everything works fine then one day I will re-try to old MAF and have a talk with the dealership if it’s still good.
     
  6. trojandnc

    trojandnc New Member

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    Called USAA and that doesn’t apply to North Carolina unfortunately.
     
  7. trojandnc

    trojandnc New Member

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    I had remembered seeing that but just put it back in and ordered one ($8) with two new studs and an intake manifold gasket.
     
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  8. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

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    I am not too familiar with California but @Raytheeagle and others used to have occasional meetups to perform Prius maintenance.
     
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  9. ASRDogman

    ASRDogman Senior Member

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    That's a bummer! Sorry...
    Well, I'd bet you won't let that happen again. :) It's part of learning.....
    We've all done something like that before.

     
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  10. Raytheeagle

    Raytheeagle Senior Member

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    That's down south;).

    Nice location too:).

    I'm still keeping my social distance and encouraging others to do the same for now, so no meet ups for me(y).
     
  11. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

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    You also got rid of your Prius that needed the maintenance. ;)
     
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  12. Raytheeagle

    Raytheeagle Senior Member

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    Even the Prime needs maintenance;).

    Sometimes it's preventative :).

    Sometimes not too early to do so(y).
     
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  13. FriedCells

    FriedCells Member

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    Just an update on my post 424 above. After another 250 miles, still no more code and I'm now reaching 50mpg right on the nose over the last 250 miles. No change in driving habits. Never hit 50mpg in 4 years of owning this car. 48 was usually my max. That makes a total of 2,000 miles after the EGR/intake/PCV/OCC work for the car to start optimizing and reading correctly the mpg's. Maybe after another 500 miles, I'll be higher still. Will see. But good for people to know not to panic with worse MPG's and a P0101 MAF code after doing the EGR, etc cleaning. Seems like it can take a good 2,000+ miles to get all those changes sorted out in the system.
     
  14. Scarface2005

    Scarface2005 Member

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    So I cleaned just the egr pipe on my ‘12 plug in yesterday. I vacuum cleaned as much of the egr cooler and intake manifold that I could reach with a little piece of hose taped on to a vacuum cleaner nozzle. I had to put the egr pipe and air box back in to go 60 miles to pick up some parts at a Toyota dealership. I drove down there sans wipers of course. Anyways, the knock and CEL are gone... for now. Just thought I’d mention that in a bind it seems that what I did can be a relatively easy quick fix. My car has 248k miles, but the egr pipe didn’t seem nearly as dirty as most of the ones I see on here with much lower miles. Until yesterday, no egr cleaning had ever happened.

    Also, I used a torquing screwdriver to easily remove the actual egr valve / sensor. Didn’t have to tap it with a hammer, I just used a little ‘elbow grease’. Its just a cover that I immediately put back on because it seems like very delicate electronics.

    I’m gonna tackle the intake manifold and pcv valve today, and the egr cooler tomorrow. Stopped by harbor freight and got a great little tube brush set for $5.

    anyone wanna come hang and help? It’s very green up my way, also rather cool weather.

    the photo is my vacuum cleaner hitting the egr via the egr pipe connection. Based on how dark the vacuum’s filter now is, I think it worked better than I thought it would.
     
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  15. Scarface2005

    Scarface2005 Member

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    Sorry the vacuum cleaner photo didn’t upload. Just got done doing intake manifold and pcv valve. Here’s some advice...

    clamp off BOTH throttle body coolant hoses before disconnecting either one, or you’ll get sprayed in the eyes, mouth, and nose like I did :-(.

    the little plastic wiring clamp attached to the top of the intake manifold was impossible to get off for me, so I cut it with a serrated knife, and e taped it back on... I might opt for a zip tie?
     
  16. Grit

    Grit Senior Member

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    Dang wish the invitation was known sooner, I'm on day 1 of a 5 day work vacation. At least the weather there will be cool, I'm moving into a house with a garage in the 100 degree weather. But I can get to some car maintenance on my own again. Hope all goes will with the EGR & manifold cleaning, throw in a OCC while your at it (y)
     
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  17. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    There is no reason to disconnect the throttle body coolant hoses. They have enough slack that you can lift off the throttle body and just tie it to the inverter or something.
     
  18. Scarface2005

    Scarface2005 Member

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    Dirty ... hopefully the photo uploads. Egr cooler is off. Gasket from exhaust to egr cooler is awol. Had to go with an aftermarket one from a local shop
     

    Attached Files:

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  19. ASRDogman

    ASRDogman Senior Member

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    Pressure washer oven cleaner time! (y)

     
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  20. Scarface2005

    Scarface2005 Member

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    All done! Still no wipers.... bc on my test drive I got p106A, something related to the MAP sensor. I don’t have the CEL light on, but it’s showing pending/monitor on my obd reader. Any thoughts? I spilled coolant all over, I’m sure some got on the MAP. I reckon I’ll give it a couple days before I break down and get a new MAP.
    But, thank God, she’s running great!!!!

    Nutz’ videos are the lifesaver for us turd generation Prius owners!:)
     
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