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High oil consumption. But WHERE is it going?

Discussion in 'Gen 2 Prius Main Forum' started by Prius92, Apr 18, 2023.

  1. Prius92

    Prius92 Member

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    My 08 went from using a quart every 6-7,000 miles at around 175,000 miles, to a quart every 500-800 miles at 196,000 miles.

    No leaks on driveway. Put white cardboard under it for 36 hours straight. Don't see any leaks around seals, oil filter, drain plug, valve cover, etc.
    Tailpipe isn't "sooty".
    No oil in coolant.
    No lights on.
    Did a piston soak, no improvement.
    Changed PCV valve, no improvement.
    Spark plugs are all normal looking with about 40k on them. No signs of oil fouling.

    My only guess is extremely bad blow-by, which would explain the oil smelling gassy a lot. In fact it smells gassy right after changing it.

    I also drive mainly highway, I'd say 80% highway, 20% city.

    So what are my options here? Junkyards have become stuck on crack since the pandemic, most near me want $1100 for a USED engine with 150-170,000 miles. 5 years ago 4 cylinders like these were $300 all day long.

    I can get a complete rebuild kit with pistons, timing chains, gaskets, rings, bearings, etc for $400 shipped. I have a full tool set including digital torque wrenches plus an engine stand.

    I'm guessing another $500 or so to have it cleaned, honed, etc.

    Traction battery was rebuilt a year ago by me, and body is solid, zero rust. So no sense in replacing the car itself.
     
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  2. rjparker

    rjparker Tu Humilde Sirviente

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    There is a reason gen2 catalytic converters are so popular, they work very well and cleanly burn off the oil.

    Gen3s do the same thing but don't have to be as good at the cat since they recirculate some of it through an egr system your gen2 does not have.
     
  3. PriusCamper

    PriusCamper Senior Member

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    Did your MPG go down as oil burn rate went up?

    Because a used low mileage Prius engine with warranty from a wrecker costs less that $1000. I'd recommend saving yourself a huge amount of time and just do an engine swap...

    There's a guy near you in Oklahoma who puts Gen4 engines in Gen3 Prius in only a day for $1500 in labor and a Gen2 engine is way more simple than what he has to do. So this whole situation could potentially be solved by you in a day once your oil burn rate gets worse...

    These two dudes did a Gen2 engine in 6 hours and his engine only cost him $450:

     
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  4. Prius92

    Prius92 Member

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    For w/e reason junkyards round me have doubled in price since the pandemic.
     
  5. Kaptainkid1

    Kaptainkid1 Active Member

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    What did you uses to do the Piston soak did you uses Berryman's B12? Leave 4 Oz in each Piston for 8 hours and rotate the Pistons 20 times for 3 intervals? Rotating the engine with B-12 in the block is very important to freeing up the sludge.


    The main reason for oil burning on well maintained 2nd gen Prius is stuck oil rings. The oil burns off into the exhaust.
    Freeing up the oil rings helps.
    I did a write up on my experience and I was able to free up the sluddgy rings.


    https://r.tapatalk.com/shareLink/topic?url=https://priuschat.com/threads/200k-2009-prius-with-oil-burning-at-1qt-for-1000-miles-highway-and-less-burning-in-stop-and-go.233081/&share_tid=233081&share_fid=1171&share_type=t&link_source=app

    SM-A536U ?
     
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  6. PriusCamper

    PriusCamper Senior Member

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    You're very central to a great number of other regions... The amount of time you spend searching for a good price on an engine to swap will be less than the time you spend rebuilding it.
     
  7. Aegean

    Aegean Active Member

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    I can think two items. Since the PCV valve is new, are the passages clear?

    Before you consider rebuilding or replacing the ICE, have you done a compression test? Or even better a “Cylinder leak down” test?
     
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  8. Kaptainkid1

    Kaptainkid1 Active Member

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    I was burning 1 qt per 1000 miles and drop it down to 1/4 qt after doing a proper Piston soak.. It took 3 different trys and last one worked for me. I'm at 205k now. She stop burning oil for the last 5k. I figured I would need to do another Piston soak every oil change until the suck rings get completely clean. It seems either after the 1st soak the rings become stuck again and that lasted 7k miles. I'm on my second Piston soak and I'm only at 3k and I'm guessing it might be stuck by 7k. Will do a follow up on my next oil change.

    SM-A536U ?
     
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  9. ColoradoCrow

    ColoradoCrow Active Member

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    Man 6 hrs for 2 people who know what they are doing is awesome. I've looked into JDM Engines on ebay, is there any way to request the oes with higher VIN's with updated pistons and rings?
     
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  10. Mendel Leisk

    Mendel Leisk Senior Member

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    Was this a thing with second gen too? With third gen the piston rings started out as "lower tension", then sometime through model year 2014 both the rings and pistons were revised (due to oil consumption reports). I've not heard of a similar scenario with second gen though.
     
  11. ColoradoCrow

    ColoradoCrow Active Member

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    Mendel.. No sorry was talking about Gen 3 but I guess I should have written that.:oops::oops:
     
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  12. rjparker

    rjparker Tu Humilde Sirviente

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    JDM engines don't have VINs. VINs are more of a US thing. However most salvage yards remove them from US engines because they allow mileage and stolen car tracking.

    Not sure low tension rings were used in the 2004-2009 Prii because they were designed earlier than other 2006 Toyota models which did have poorly designed low tension rings. Various Toyota and Subaru models from 06-15 had problems with them. As I understand it, it is the implementation of low tension rings more than the rings themselves. Gen2s with high miles often burn oil for normal reasons.

    Poorly designed low tension pistons and rings have a tendency to allow blowby. You then have contaminated oil lubricating the rings and causing deposits. Toyota endorsed 10,000 mile oil changes with the first two free made things worse. Eventually the deposits get worse and the rings don't seal as well as they used to, allowing more fuel and combustion gasses to enter the crankcase. Then the pcv and egr systems (gen3) picks up more oil and you have carbon everywhere increasing fast. The uber effective catalytic converters prevent white smoke.

    87E286B1-EDEA-4AB3-883D-E5D47B55AD41.jpeg
     
    #12 rjparker, Apr 20, 2023
    Last edited: Apr 20, 2023
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  13. PriusCamper

    PriusCamper Senior Member

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    No issues with Gen2... Bad rings and gasket are just rare as catastrophic engine failure... Of course bad rings up near 400K miles is unavoidable for any gasoline engine.
     
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  14. Prius92

    Prius92 Member

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    I'm reading the cylinder block from a newer Yaris will fit the GenII prius.
    I know the entire engine won't swap because it's made a bit different.
    But I'm curious what else will change over?
     
  15. PriusCamper

    PriusCamper Senior Member

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    That sure would be cool if true... I know they both have the same oil pan as well... Of course sitting them side by side for lots of measuring to be certain if you're gonna use a Yaris Head, unless the person selling the head has already confirmed...

    I'm also working on the theory that 2012 Toyota Corolla has the same fronts seat as a Gen2 Prius... Can anyone confirm that too?
     
  16. Mendel Leisk

    Mendel Leisk Senior Member

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  17. ColoradoCrow

    ColoradoCrow Active Member

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  18. PriusCamper

    PriusCamper Senior Member

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  19. Prius92

    Prius92 Member

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    That's the electrical assist engine, not the main gasoline engine.
     
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  20. Prius92

    Prius92 Member

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    Well this sucks. There is a ton of confusing interchange information online about what parts fit what engine.
    If you go on eBay, you will see a head from a 2015 Yaris 1.5 rebuilt, "fits Prius".
    But then I read the heads are slightly different, now I'm reading the block is "slightly different".