2.5 Quarts low after 8300 miles, ok to drive?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by zm15, May 9, 2016.

  1. zm15

    zm15 Junior Member

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    I recently returned from a 500+ miles roadtrip in which the low oil pressure light blipped on twice. It happened so fast that I couldn't even tell what it was the first time, I thought it was the tires. So i stopped, checked the tires and kept driving, about another 100 miles until I got home. The second time it blipped very quickly again but I caught a glance this time and it was the 'low oil pressure' light.

    When I got home I checked the dipstick right away and there was no oil on it, only a thick, copper colored type residue with what appeared to be little flakes. I put oil in until it reached the middle of the dipstick, which was 2.5 quarts.

    I didn't hear the engine making any funny noises or anything out of the ordinary when driving. I put the new oil in and it started fine and sounds normal.

    Should I be worried about any damage to the engine? Other than burning so much oil?
     
  2. JC91006

    JC91006 Senior Member

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    What's done is already done. Just keep an eye on the oil level as it may start burning more than 2.5 quarters in 8000 miles now.
     
  3. mrbigh

    mrbigh Prius Absolutum Dominium

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    2.5 quarts is a very high oil consumption. How many miles the vehicle has? First owner?
     
  4. frodoz737

    frodoz737 Top Wrench

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    Yes you will continue to burn oil. As I have done and recommend since I was 17yo, check your oil every fill up...or more as the situation dictates. Dealership screwed up on mine and I lost +3 liters in 400 miles...which they owned up to and extended the engine warranty (already expired) an additional 100,000 miles. Did my oil/filter change every 5,000 miles prior and never indicated oil loss. Now it burns oil. May still be getting a new motor.
     
  5. zm15

    zm15 Junior Member

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    108k miles, bought it with 35k on it.

    I think it's been burning for awhile as I recall checking the dipstick in previous years and not seeing it in the middle. I need to do a better job of checking it more consistently.

    What causes an engine to burn oil in the first place? And why will it continue to burn with sufficient oil?
     
  6. Mendel Leisk

    Mendel Leisk Senior Member

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    The difference between the two marks on the dipstick is 1.6 US quarts. So if it took 2.5 quarts to get level to the mid-point, you were more like 3.3 quarts low. Fully drained without filter change, it'll take 4.1 US quarts to put it on the top mark of the dipstick, so you likely had about 0.8 quarts remaining in the sump, plus about 0.3 quart in the filter housing.

    Very low, but better than nothing.
     
  7. frodoz737

    frodoz737 Top Wrench

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    Barely...if you mean it didn't seize or have a come apart.
     
  8. DoubleDAZ

    DoubleDAZ Senior Member

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    The engine "burns" oil because something is allowing oil to seep into the combustion chamber, usually a problem with the piston rings, etc. The engine might be "losing" oil through a leak, like the drain plug missing the washer, the oil pan gasket leaking, etc. While it might be acceptable to some to be down a quart between oil changes, losing almost all the oil in 8,000 miles would bother the heck out of me. We drive at least 6,000 miles every time we take a trip, 3 times a year, and I can't imagine having to put oil in multiple times during those trips.
     
  9. Mendel Leisk

    Mendel Leisk Senior Member

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    Or doubled-up (or tripled-up) drain bolt washer? For me the drill now is to back out the drain bolt a few turns, then take a slim bladed screwdriver and hammer, and break loose the washer. It's always firmly bonded to the oil pan.
     
  10. zm15

    zm15 Junior Member

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    I don't have any oil leaking underneath (that is visible on the garage floor anyway), so it must be burning in the engine.
     
  11. bisco

    bisco cookie crumbler

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    you can find a couple good threads here on 2010's starting to burn oil around 100,000 miles, and possible solutions. i would check it ever 100 miles until you get a feel for how quickly it's burning. fill it to the upper mark, and don't let it go past halfway to the lower. all the best!(y)
     
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  12. Kenny94945

    Kenny94945 Active Member

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    Good advise above....check your oil level more often.
    Plus post 11 ...offers a lead for searches on this forum for similar issues.

    I have found some manufacturers say 1 quart every 1000 miles is OK and fight inquiries/ warranties and do nothing at that level...but to me personally that is excessive.

    Reasons for oil use...worn rings, worn valve stem seals/ guides are two major ones.
    Leaks and oil in the PVC system recirculating back to the intake two others.
    Incorrect oil level from your last oil change is certainly not to be ruled out.

    If you are mechanical, do a compression test and a leakdown test to offer some diagnosis.

    Good luck wished.
     
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  13. zm15

    zm15 Junior Member

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    Thanks a bunch everyone! Really appreciate the insight. I drive about 80% highway miles, so need to remember to check the dipstick more often between stops.

    As far as a compression test, I'd like to try this, best threads to learn how to do this by chance?
     
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  14. bisco

    bisco cookie crumbler

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    a reasonable solution, if you get tired of adding oil, or the engine problems get worse, is to find a local mech who will install a low mileage salvage engine. they are cheap, because the demand is very low.
     
  15. CR94

    CR94 Senior Member

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    I'd certainly worry if I found flakes of chewed-up metal in the oil due to running the engine almost out of oil. There may be a lot more such flakes caught in the filter, so it needs changing ASAP.
     
  16. zm15

    zm15 Junior Member

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    i should clarify, at the verrrry end of the dipstick there were the tiny little particles, at least they appeared to be shiny particles. I think it's a good idea to submit a sample from my oil change. I can't recall, what is the name of the company where you submit a sample to?
     
  17. mmmodem

    mmmodem Taste Tester

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    Contrary to the other replies on here. I don't think losing a quart every 3000 odd miles is that bad. I had a car that burned a quart every 300 miles when I was a teenager. It was very easy to top off a quart every tank than pay for engine repair.

    I'd start switching to high mileage oil, thicker oil or changing to a 5000 mile OCI to see if things get better. Should you be worried about engine damage? Why? It won't make it any better. What's done is done. Keep a quart of oil in your trunk and check the level every time you get gas.
     
  18. Mendel Leisk

    Mendel Leisk Senior Member

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    One thing, with high mileage oil, there's no going back: it basically swells rubber valve guides. If you switch to regular oil they'll shrink with a vengeance. At this juncture maybe not the end of the world, just something to be aware of.
     
  19. bisco

    bisco cookie crumbler

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  20. DoubleDAZ

    DoubleDAZ Senior Member

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    IMHO, it's very difficult to diagnose this over the internet. If it were me, I'd be checking the oil quite often to see what's going on, especially if I wasn't going out of town for awhile. The best time to check the oil is after the car has set for awhile, like overnight. If mileage is unchanged and there's not a noticeable difference in performance, then maybe it's not a serious mechanical failure. Using 2.5 quarts over 8,000 miles is around a quart every 3,000 miles or so. That was acceptable back in the days of 3,000 mile oil change intervals, and why we tended to check the oil with every fill-up, but it's not something I'd be happy with today. I can't remember the last time I had to add any oil between changes. I think it was on a used 1963 Ford back in 1968. ;)

    I am bothered by the comment that the dipstick has been checked before and found to be below the mid point. Apparently that didn't trigger a mental note to check the oil more often. :) But, the mid point is not the full point. Most dipsticks measure around a quart of oil between Low/Add and Full. So starting at mid point is already a half quart low in my book. Might not be bad if it stayed at that level, but if it's using oil, that simply shortens the time needed to get to a full quart low or lower. I'd also be looking at the quality of the oil on the dipstick and how long it stays looking like new.
     
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