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Oil Pooling in Intake Manifold

Discussion in 'Gen 1 Prius Plug-in 2012-2015' started by xmooneydriver, Mar 8, 2018.

  1. xmooneydriver

    xmooneydriver Junior Member

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    I have a 2012 Prius PlugIn Advanced that I have had new since Dec 2012 (5 + years) with 63,000 miles. I took it in for the fuse recall and I was informed after the warranty work was done that I need to have the intake manifold cleaned due to oil pooling. I was further informed that this would cost $511, much to my chagrin further research unveiled a video that showed a mechanic doing the whole process in 41 minutes albeit some parts where nuts were spun off were accelerated. So round it up to 1.5 hours. A new intake gasket and pcv valve are $15. What is the dealer doing for the extra 3.5 hours that he is charging? I researched it on the web and what I found that this cleaning is recommended between 100k and 120k miles. I also found that this can be caused by overfilling of oil. I looked at the dip stick and found it was overfilled by about 3/8 of an inch. Dealer has changed oil since day one. I have contacted the service manager and discussed the oil overfill and the oil pooling issue. I also asked him to explain the $511 where the video shows it can be done in 1.5 hours and $15 in parts. Note when the intake manifold is cleaned it is also a good time to replace the pcv valve as the same disassembly is required.

    So my questions are ...

    1. Does anyone else have experience with this problem with prius plugins?
    2. Can the 3/8" overfill cause this or exacerbate the pooling?
    3. This is happening way too early can something else be wrong?
    4. What have other people paid dealers for this service?

    Here is the link to the video for full disassembly, cleaning and reassembly of the intake manifold.



    btw I called the service manager, he confirmed that he has received the email along with the link, picture of my dipstick showing overfill and he said he would get back to me once he reviewed it during a quiet moment. 1 week and counting...
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    That video, and a whole wack more, are by member @NutzAboutBolts , have been linked in a thread pinned at the top of the 3rd gen maintenance forum:

    Nutz About Bolts Prius Maintenance Videos | PriusChat

    Yeah, it's a common third gen "issue", not just the Plug-In, which is essentially a third gen for the most part.(note you've posted in 4th gen Prime forum), and cleaning is something you can fairly easily do yourself.

    The apparent culprits are likely oil/gas/water being introduced by the PCV valve, for the most part, and to a lesser degree a bit of "spit up" coming the from the intake ports, maybe just the nature of Atkinson Cycle engines? I'm out of my depth what an AC engine is, but I have seen an oil trickle from each intake port, when I had ours off.

    I would suggest:

    1. Clean the intake manifold.
    2. Install an Oil Catch Can, in series, along the hose between PCV valve and intake manifold.
    3. Clean the EGR circuit, stem to stern.

    For item 3, again, there's a video on that subject, in the above link.
     
    #2 Mendel Leisk, Mar 8, 2018
    Last edited: Mar 8, 2018
  3. Bob Comer

    Bob Comer Active Member

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    The dealer tried the same thing with me and my My Gen 3 Prius (2010). I was at about 150,000 miles. Everything was running fine, so I didn't get it done.
     
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  4. bisco

    bisco cookie crumbler

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    welcome!
    63,000 sounds very early. i have 55k, but do not know how to check it.
    i always syphon out the extra oil after an oil change. again, not sure if that is part of the problem.
    how would the dealer go about looking for oil pooling during a fuse replacement? i have not read about any plug ins having the issue, but do agree that after 100k, it might be possible.
     
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  5. Mendel Leisk

    Mendel Leisk Senior Member

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    Watch @NutzAboutBolts video (maintenance sub-forum) on throttle body cleaning, it shows the steps to get to the throttle body. Just pushing open the throttle blade and looking through, you can get a fair view. Removing two bolts and two nuts, you can lift the throttle body right off (leave coolant hoses attached, they have enough play), and get a much better view. Torque for both the nuts and bolts is 7 ft/lb.

    Only thing, it hardly needs checking: it's pretty much for certain there will be a swimming pool there, depending on the time of year either mostly oil, or a mix of oil/gas/water.

    There's the MAP sensor just to the right of thottle body while your're there, you can disconnect unbolt and remove. It'll likely be oil drenched. MAF sensor cleaner should be safe for it. It seems pretty sturdy, but do go easy on it: it sells for somewhere around $200 IIRC.

    You could swab it out, but without a Oil Catch Can on the PCV circuit it'll back as it was soon enough. Perphaps even with OCC: I'll take a look at ours come spring to check. There is a bit of oil spit back from the intake ports, that the OCC doesn't deal with. I think not as much though. I hope.
     
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  6. bisco

    bisco cookie crumbler

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    do you think some dealers are now savvy enough to check all gen 3's when they come in? new profit center, i suppose.
     
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  7. Bob Comer

    Bob Comer Active Member

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    They probably do it for all vehicles.

    I once owned a car with throttle-body fuel injection, and the gunk in the intake manifold really did make a big difference, so I suppose it's not out of the realm of possibility for some cars to be more sensitive to it than others.
     
  8. Mendel Leisk

    Mendel Leisk Senior Member

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    The EGR passages within the intake manifold are prone to gunking up too.
     
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  9. xmooneydriver

    xmooneydriver Junior Member

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    Thank you Mendel very helpful.
    .
     
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  10. bisco

    bisco cookie crumbler

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    what happens if you don't clean it until you have symptoms?
     
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  11. Mendel Leisk

    Mendel Leisk Senior Member

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    There's nothing conclusive, but I've heard a properly functioning EGR is helping to keep the engine cooler. And if the engine's running hotter, there more chance of head gasket failure??

    Again speculation, but maybe what the PCV valve is dumping into the intake manifold, is getting sucked into the combustion chamber, and then back into the EGR, accelerating it's clogging???
     
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  12. danlatu

    danlatu Senior Member

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    You get engine knock from oil/water/fuel sucking into the combustion chamber. We had that happen @72k on our 2010. Intake manifold cleaning with a blue shop rag and oil catch can fixed the problem. I just pulled the intake tube off and opened the throttle body, pushed the rag in past the throttle plate and swabbed it to soak up the standing oil. I did not remove the intake manifold at all. Our 2010 has 122k, our 2011 has 312k with no knock and no oil burn, both cars run great. My 2011 has more interior noise due to miles. Thats really my only complaint.
     
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  13. Mendel Leisk

    Mendel Leisk Senior Member

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    I would unbolt and pull off the throttle body for that operation. It's not hard, and you just need to disconnect one electrical connector. You can leave the coolant hoses attached, and just lift it up and out of the way. The throttle body bolts/nuts torque is 7 foot pounds (84 inch pounds).
     
  14. bisco

    bisco cookie crumbler

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    also, how many of your 63k are hv miles?
     
  15. Ralph skelley

    Ralph skelley Junior Member

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    I had a 2005 prius. The dealer cleaned the throttle body. A couple of thousand miles later, it would not start. It was towed to the dealer. They replaced the throttle body for $1200 plus. Now I have a 2013 Prius V with 60K. Now they tell me the PVC is sticking and the intake and the MAF sensor needs cleaning. I'm afraid to have them touch it.
     
  16. Mendel Leisk

    Mendel Leisk Senior Member

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    Just out of curiousity I looked up the price of the throttle body: $385.54 (US), through McGeorge Toyota:

    2001-2009 Toyota Prius Throttle Body 22030-21020 | McGeorge Toyota Parts

    Unless it's completely different than 3rd gen, replacement is a simple job, one hour at most. Where there other things done. If that was it, it's a rip.
     
  17. audiodave

    audiodave Active Member

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  18. Mendel Leisk

    Mendel Leisk Senior Member

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    The PCV valve is around $10 to replace. It's easier to do if the intake manifold is pulled off, but you can it from below, just taking off the engine underpanel. The MAF sensor is very easy to clean yourself: get a can of CRC MAF sensor cleaner, and watch their video.

    It's very likely both those items are ok though, sounds like your dealership might just be trying to drum up business.
     
  19. Mendel Leisk

    Mendel Leisk Senior Member

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