drained oil filter, not main oil tank

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Pups, May 28, 2025 at 2:22 PM.

  1. Pups

    Pups New Member

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    First, I changed my oil 20k miles ago and idiotically only drained the oil from the filter compartment (based on the amount of oil that came out, I thought my car was burning too much oil). Replaced filter, added new oil, about 4qts

    yesterday at the 10k interval, again I did the same thing :( changed filter, noticed very little oil from the filter compartment...dipstick was all over the place and I must have been having a covid brain fog fart because I thought maybe because the engine bay is hot so it wasn't sitting right. added another 4 qts of oil.

    drove today to take my dog to the vet for a surgery and on the way back, I noticed white smoke. I thought to myself, can't be my car I take good care of it and change oil every 10k miles. Then while exiting the freeway on the offramp, I saw more smoke. and I thought I must have drove over some dirt and stirred it up.

    and then when accelerating from a stop light, I saw White smoke and I said, crap it's my car and something isn't right. Came home, looked online and it said White smoke can indicate overfilling your oil. Then I had a flash back that 20k miles ago, I drained the oil from the filter compartment. and then after 10k miles (yesterday) I did the same thing. So my oil reservoir must be FULL. I let the car cool down, looked at the dipstick and noticed the oil level was 3-4 times higher than the full indicator...

    so... now I went and bought some more 0w-20 and plan to flush out the oil completely. and then put new oil.

    I have a few questions
    1. should I replace the filter even though I replaced it yesterday and only drove maybe 20 miles?
    2. should I put seafood or liqui moly to clean out the engine?
    3. should I do the next replacement at 5k miles instead of 10k just to flush out any buildup from the past 2 oil changes?

    I'm not dumb, I really, really, really blanked out on the oil change.
     
  2. Brian1954

    Brian1954 Senior Member

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    1. I would reuse the filter, but you need to unscrew the filter to drain the old oil.
    2. I can not give you my opinion since you did not say how many miles are on the car.
    3. General opinion on this forum is to do 5k mile oil changes every time rather than 10k recommend by Toyota.

    You should check your oil level after changing the oil and every other fill-up of the gas tank.
     
  3. Pups

    Pups New Member

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    Hi Brian, thanks for your response. I had to pick my dog from the vet and didn't see your message, so I drained the oil from the tank but not the filter... I'll do a 5k service next.

    I did edit my comment to add that it's a 2011 Prius with 130k miles, but looks like my post was under admin review and the change didn't save.

    And LoL, I didn't mean to put "seafood" in my engine, I meant Seafoam.. although I did have seafood for lunch today so I'm not sure if it autocorrected, or if I actually typed that because I was hungry.
     
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  4. Grit

    Grit Senior Member

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    So are you going to flush out the oil by removing the oil filter?
     
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    Can you clarify: you only drained oil by removing the oil filter, you didn’t remove the oil pan drain plug, for two oil changes now? If so you likely have close to triple the spec'd quantity of oil in your engine. Have a look at the attachment:
     

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    #5 Mendel Leisk, May 29, 2025 at 10:35 AM
    Last edited: May 29, 2025 at 12:36 PM
  6. Danno5060

    Danno5060 Active Member

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    I'm not sure of your intervals - 20k, or 10k. It also sounds like your only partially changing your oil - with just emptying the filter, or oil pan, but it sounds like you've not done the complete job either time.

    If that's the case, definitely drain the oil pan and change the filter, and put some quality stuff in there - as well as getting it on a 5K interval. At least that's my opinion and what I do for my cars.
     
  7. BiomedO1

    BiomedO1 Senior Member

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    Sorry; you seem to be "all over the place".
    Please clarify your procedures and what your actually doing to the car. All this personnel stuff is confusing the matter at hand.
    FWIW; white smoke out the exhaust has nothing to do with oil level - your burning coolant and you should have a noticeable misfire. Since you didn't mention that; or check coolant levels - you should probably take the car to a professional to get it diagnosed properly.

    YMMV...
     
  8. rjparker

    rjparker Tu Humilde Sirviente

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    This story is hard to believe especially if it was repeated several times.

    Do you now know where the oil drain bolt is on the bottom of the engine?

    You changed your oil filter a couple of times in a row without draining the oil pan, each time adding 4 quarts of oil. Since most of the oil is lower than the filter, you probably drained no more than one quart each time.

    You ended up with 8-12 quarts of oil in the engine for a period of 10k or more miles.

    Most likely the oil was flowing through the pcv valve into the intake and burning causing the white smoke. If you are lucky.

    I would be surprised if you have not blown some seals such as the form a gasket on the timing chain cover which might then dump oil on the hot engine and catalytic converter. Hopefully not.

    @Grit This has to be a new one for the files
     

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    #8 rjparker, May 29, 2025 at 12:55 PM
    Last edited: May 29, 2025 at 1:19 PM
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  9. Pups

    Pups New Member

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    okay, here is the tl;dr version.

    I have been changing the oil in my prius for over 10 years without issues
    I know where the filter and drain plug is.
    I change the oil every 10k miles, no issues with the car
    20k miles ago I drained the filter reservoir and changed my filter. I did not drain the main tank. then I filled the top with 4 qts of oil.
    then, this weekend 10k miles later, I did the same thing. (all my intervals for past 5 years at least have been at 10k miles)
    I drove about 20 miles after this oil change and noticed white smoke during acceleration from a stop. I also did notice slow acceleration of the car.

    I looked online and read a post that white smoke could be caused by too much oil ( I searched for this exact terms "prius white smoke after oil change exhaust acceleration" it is the 3rd possible cause listed there:
    1. Blown Head Gasket
    2. Water in Fuel or Oil
    3. Excess oil

    I came back, let the car rest then checked the dipstick here is the pic: [​IMG]
    I drained the oil from the main tank - it filled (1) 5qt jug, almost (3) 2qt jugs (so about 11qts of oil came out)
    I didn't change the filter this time or drain the oil from the filter reservoir
    I closed the drain plug and filled the oil back with 4.4qts of new Mobil 1 0w-20 oil which is what I always use.

    Drove the car, white smoke was gone. no check engine light and no slow acceleration.

    @rjparker I assure you this isn't a story, it's facts :( I messed up. but looks like my car survived. I've been taking good care of it for 14 years, just had severe brain fog on how to change the oil.

    to clarify what I mean about 20k miles ago, I mean to say I've been changing my oil every 10k miles. but 2 oil changes ago (20k miles ago) I didn't drain the plug. then this past weekend after driving 10k miles from my last oil change, I made the same mistake. so every oil change has been at 10k miles. But after this last oil change, I drained 11qts of oil (2 old oil cycles plus 1 new oil cycle) and then filled 4.4 qts of new oil. So what's in my car right now is 4.4qts of new oil and however much oil may have been in the filter reservoir that I didn't change.
     
    #9 Pups, May 30, 2025 at 2:55 AM
    Last edited: May 30, 2025 at 3:02 AM
  10. RRxing

    RRxing Senior Member

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    Some folks should not work on cars.
     
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  11. bisco

    bisco cookie crumbler

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    :eek: don't you check the dipstick when finished?
     
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  12. rjparker

    rjparker Tu Humilde Sirviente

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    The confusion on our end started with the above description of sequence of events.

    I might have said "The last three 10k mile oil changes all I did was replace the filter and add 4 quarts of oil. I ended up burning white smoke so I drained it and found 11 quarts were in there."

    So it sounds like you dodged a bullet assuming no more smoke. Actually it appears you are not even burning oil in the traditional way.
     
    #12 rjparker, May 30, 2025 at 2:44 PM
    Last edited: May 30, 2025 at 3:31 PM
  13. Mendel Leisk

    Mendel Leisk Senior Member

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    Just doing a bit of extrapolation, looks like (very) roughly 2.6 (US) quart overfill:

    upload_2025-5-30_11-59-40.png
     
    #13 Mendel Leisk, May 30, 2025 at 2:59 PM
    Last edited: May 30, 2025 at 3:11 PM
  14. Mendel Leisk

    Mendel Leisk Senior Member

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    You're using terminology that's a head scratcher. The preponderance of the oil is in the oil pan, aka oil sump. It's got the drain bolt on the underside back corner.

    Then there's the oil filter. There's not really any "reservoir" there. When you remove the filter about a cup, at most, spills out.
     
  15. rjparker

    rjparker Tu Humilde Sirviente

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    He said he drained 11 quarts.
     
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  16. Mendel Leisk

    Mendel Leisk Senior Member

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    Just going by the dipstick pic, and assuming nothing's been drained and it's a good reading, on level ground: If oil was at dipstick top mark he'd theoretically drain 4.5 US quarts. That dipstick is indicating roughly 2.5 quart overfill, so say 7 quarts drain.

    Whatever, it is gross overfill.
     
  17. rjparker

    rjparker Tu Humilde Sirviente

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    I think the dipstick is not intended for a 7 qt overfill. Obviously there is more room in the upper oil pan than in the calibrated lower section.
     
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  18. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah was thinking about that too.
     
  19. ASRDogman

    ASRDogman Senior Member

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    "I did not drain the main tank."
    There is NO such thing on a Prius, or car.

    You've not been very clear on just what you have been doing.

    You have a drain plug on the engine oil pan. That's where you drain the engine oil.
    Then you have the oil filter housing, where the oil filter is.
    They are close to each other underneath the car.
    You can remove the oil filter housing and let that drain while you are letting the
    engine oil drain.
    Then you can replace the filter and "O" ring, and install a new TOYOTA filter, and
    reinstall the housing.
    Then replace the drain plug seal and reinstall the plug.
    Then fill the engine with 4.5qts of synthetic 0W20 oil.
    Start the car and let the engine kick on and let it run until it shuts off. Wait a minute then
    check the oil level....

    You should do this every 5000 miles......


     
  20. bisco

    bisco cookie crumbler

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    this is an entertaining thread :cool: