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Excessive Oil Consuption Significantly Worse in 2010 Model?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by bchaney, May 23, 2015.

  1. JC91006

    JC91006 Senior Member

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    Kbeck, so the cars that are locally driven should have more engine wear?
     
  2. kbeck

    kbeck Active Member

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    So: If you have a conventional car with a conventional engine, and engage in short trips, yep. Bad gas mileage and increased wear.

    For that matter, if I'm not mistaken, they say that in the Prius manual, too: Change your oil more often when you do lots of short trips.

    Now, that's mainly explained as "short trips when the engine is cold." But "engine is cold" is the same as "oil is cold", and cold oil doesn't as readily form that nifty lubricating film and "wave" in the journal bearings. I also suspect that cold oil under high pressure degrades (as in, breaks chemical bonds), and short hydrocarbon chains don't do as good a job as a lubricant as long hydrocarbon chains.

    KBeck
     
  3. R2T2

    R2T2 Junior Member

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    I have a 2010 I just purchased about 2 or 3 months ago. 160,000 miles. The dealer said they changed the oil when I purchased it. I have just driven it 5000 miles and I added a quart of oil several weeks ago and the oil level is now just above the oil dipstick lower dimple for needing another quart. It was time for a change so I just had it changed. The mechanic cleaned the intake manifold and some of the egr system which I had already cleaned. He said I was getting significant oil blowback through the rings and that was where my oil consumption was coming from.

    I am concerned about this excessive oil use and what it might be doing to other engine components. Any thoughts or suggestions about what to do?
     
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

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    1. When you added a quart of oil, how low was the oil dipstick reading prior to your adding the oil, and what did the dipstick reading rise to after allowing time for the newly added oil to drain down to the crankcase? What is the viscosity of the oil that you had added?
    2. What oil viscosity are you now using with the most recent oil change?
    3. One possible action to reduce the oil consumption rate is to increase the oil viscosity. For example if you had been using the correct 0W-20 full synthetic oil, start using 10W-30 synthetic oil especially during hot summer months.
     
  5. bisco

    bisco cookie crumbler

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    when you buy a car with 160,000 miles, you have no idea how it was driven or maintained. thus, there is no reflection on the design/build quality or components.
     
  6. R2T2

    R2T2 Junior Member

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    1. The oil reading was right at the lower dimple when I added oil. I think it raised to the upper dimple, but don't remember. I added 0w 20 Mobile One.

    On the adise of my mechanic, I agreed for him to put in 10W 30.

    So maybe 10w 30 will help. I plan to keep a close eye on it and see.
     
  7. R2T2

    R2T2 Junior Member

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    Agreed. I don't know how it was mantained.. I was taking a chance.
     
  8. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    The Prius dipstick is 1.6 quarts between the two dimples. If you were at the bottom dimple and add a quart you're certainly fine for a while.

    Did you check your oil level just when you bought it? If not you're still kinda in the dark, as to how much it's consuming. Keep an eye on it for a while.

    The Prius dipstick is hard to read, I find. Smears a lot. Flip it over, check both sides, do multiple checks, look real close with good light, you'll eventually get an "idea" what the level is, lol. Doesn't help that the oil stays very clean looking.

    160,000 miles on a 2010 is getting up there. Your mechanic sounds sincere, on it. Good luck with it.
     
  9. mracko

    mracko Junior Member

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    My experience is similar to JC91006's, I am approaching 140K on my 2010 and it has only been within the last 10 to 15K that it has started burning oil. It seems to be a quart every 4,000 miles. I will have to look into the blocked piston oil return holes that valde3 suggests. The oil consumption does have me a little concerned, but it still runs great and gets great mileage.
     
  10. valde3

    valde3 Senior Member

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    That doesn’t sound as very big oil consumption.

    Trick is to remove the spark plugs. Get the engine to about 90 degrees past TDC (all pistons in about half way). Pour solvent (diesel or something else) into cylinders. Let it sit for 24 hours or longer. Remove the access solvent from the cylinders (some of it should have gotten thought). Change the oil, put the spark plugs pack in, and start only after that.
     
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  11. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    What's the object with that? To dissolve carbon on the piston rings? Interesting.

    Seems a bit of an undertaking though. First, getting the spark plugs out on third gen, while not impossible, is not trivial. You need to take off the wipers, window trim, wiper motors, and stamped metal cowl at bottom of windshield.

    Otherwise the spark plug connectors cannot be pulled out of the spark plug wells. An inch or so more clearance and it would be possible. Maybe it's best anyway, makes it much more open.

    So after letting the diesel sit you siphon it back out, with a Mighty Vac or similar, as much as possible? It seems to me the first start up after this procedure is going to be really rough. Also, could it mess up the catalytic converter? I'm out of my depth, but think I've read accidentally pumping diesel can be disastrous: but maybe these amounts are trivial?

    Regarding spark plug access, this is what it looks like opened up. It takes about an hour, well for me anyway.

    image.jpg
     
    #51 Mendel Leisk, Jun 2, 2015
    Last edited: Jun 2, 2015
  12. R2T2

    R2T2 Junior Member

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    I checked the oil immediately after purchasing. It was up somewhere close to full dimple, but didnt pay close attention to precisely how full. Agreed that I will keep a closer eye on it. Yes the mechanic is very sincere and knowledgeable. I trust him. A long time friend and cousin. But this was the first Prius he has worked on.
     
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  13. Avi's Advanced Automotive

    Avi's Advanced Automotive Independent hybrid repair shop

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    FYI

    -The taxi cab fleet I work on seem to have oil burning issues with a few of their Gen III Prii.
    -They are adding oil very frequently.
    -Some of these had their valve stem seals replaced when I replaced the head gaskets on them.
    -Until we tear down one of these oil burning engines, all we're doing it theorizing.
    -These cabs have around 250,000 miles on them.
    -Gen I Prii seem to be immune to excessive oil burning.
    -Piston rings may have changed between Gen I and Gen II.
    -Dealers always use the highest quality and proper viscosity motor oil.
    -The line above is complete bull.
    -Toyota has an extended warranty for oil burning on other models.
    -My Gen I (370,000 miles) burns less oil in between every oil change.
    -Since I got my Gen I, at 332,000 miles, It's gotten Mobil1 5W-30 and STP motor treatment every 5K.
    -STP in the white metal can, not the blue plastic bottle.

    Avi
     
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  14. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    No (measurable) oil use at 82K.

    Of course....my beloved company changes the oil out every 5k.

    ---Just one data point.
     
  15. valde3

    valde3 Senior Member

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    I know it’s not very simple thing to do. But it’s a lot easier than engine rebuild or replacement. And I have seen stop oil consumption (make it so that you don’t have to add oil between changes) in the (older Toyota) engine that consumed 1l of oil in 2500km or quart/1500miles.

    You can vacuum the cleaner out. Or you can shoot it out by just cranking the engine with spark plugs removed (messy way) (and will require extra steps with Prius). It didn’t start very rough after this but there was hardly any diesel left. If you pour gas down in there and suck it back down there should be basically no diesel left.

    This will not damage the catalytic converter more than the amount of oil that the engine is already burning.
     
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  16. Former Member 68813

    Former Member 68813 Senior Member

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    yup, it's known as piston soak and I've done it repeatably to my oil burning corolla. it generally works with some limitations. i didn't know diesel fuel worked for that. I used MMO (bad), B12 (better) and Kreen (best). best done before oil change and with some idling in between as the cleaner that goes through the rings doubles as engine flush.
     
  17. R2T2

    R2T2 Junior Member

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    Thank you for sharing the extended warranty link. I will follow up on that. Very helpful.
     
  18. R2T2

    R2T2 Junior Member

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    Oops. Just saw the excessive oil consumption didn't include the Prius.
     
  19. Jared

    Jared Member

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    2010 Prius with 132k miles. I always changed the oil at dealer every 10k with no problem. Last few weeks I started getting beeps and low oil pressure warnings on turns and braking. I assume the oil was very low.
    I have now learned the dipstick is my friend. I check every week and I do have to top up the oil but not sure yet how frequently. The main lesson I have learned is it is not enough to do the regular oil changes - you must check the level and top up as necessary.
     
  20. CR94

    CR94 Senior Member

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    Huh?? It's not irrational to care to know what I can do, if anything, to avoid a problem so many owners apparently have when their Prii accumulate a few more miles than mine has yet. "Don't worry" isn't a good plan.