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Worried about possible oil leak

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by DrTrivia, Mar 5, 2017.

  1. DrTrivia

    DrTrivia Member

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    I've had my 2011 Prius III since it had 70k miles on it, currently on 136k. I've changed oil every 10k miles (once did it after 5k by accident), make sure I have a 15k mile oil filter in it, and use 100% synthetic oil (Mobil 1, but I doubt it makes a difference). At my last oil change I noticed that I didn't drain as much out as normal. I've driven 6,000 miles since then and checked the oil level again today. It was low by about a quart, maybe a little less. During my first several oil changes there was very little loss of oil. I have also noticed an area under the engine that looks like it might be the site of an oil leak. I tried to take a picture of the area, if it helps. I would like to try and avoid going to a shop, but if I must, then I must.

    This first picture is a close-up of the area in question. The "gunked" are is right between the two bright spots in the middle, next to that wheel. This is in the left side of the engine compartment (viewed from the front of the car). The bar code in the picture is printed on the side of the engine itself. Tried to upload a zoomed-out picture to give a better idea of the location, but can't seem to do it. The other photo is "attached".

    20170305_201528_001.jpg
     

    Attached Files:

  2. mjoo

    mjoo Senior Member

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    This could be the start of the Oil Pressure Switch leaking. AFAIK those don't normally crack. It's as simple as removing, cleaning and reinstalling with the appropriate adhesive.

    Posted via the PriusChat mobile app.
     
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  3. Mendel Leisk

    Mendel Leisk Senior Member

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    Or the timing belt cover leaking? Dealerships in the US are charging around $1700 to remove and reseal that.

    Either way, I would take the engine under panel off, check the inside, and the slab or whatever in your usual parking spot. A quart of oil leaking every 6000 miles would show more than just an oily appearance on the engine; that's significant leakage.

    I'd suspect it's just burning some. A quart every 6000 miles is not bad. Check the dipstick a bit more often, and if you want you could try switching to 5W30, see what that does.
     
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  4. Raytheeagle

    Raytheeagle Senior Member

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    Your car is starting to develop a drinking problem:(.

    But the good thing is you are aware of it;). Now the fun begins.

    In addition to what @Mendel Leisk suggests above (which what I have done for 30 k miles with reduction in oil consumption), I also have slowed my driving speed down by 5 mph as I do 38 miles one way to work.

    Not a lot but enough to help(y)
     
  5. MeGuinness

    MeGuinness Member

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    Did u find out what the problem is ?I'm having same problem.

    Posted via the PriusChat mobile app.
     
  6. bisco

    bisco cookie crumbler

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    is everyone checking the dipstick routinely? what is a 15k oil filter?
     
  7. DrTrivia

    DrTrivia Member

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    I believe the problem is a leak around the Oil Pressure Switch, as suggested by Mjoo. That seems to be the area the problem is concentrated in. Likely a combination of that and the fact I need to be better about topping it off every few thousand miles. Unfortunately, I have been unable to verify this as of yet. I did my last oil change about 2 weeks ago, and since I was in a hurry, I completely forgot to remove/clean the Oil Pressure Switch. Doh! I'm going to see where my level is at in another 3k-5k, and if I feel it is especially low, I'll do another oil change early and service that part. If I find any other issues, or can confirm the oil pressure switch was a problem, I'll post it here, but I won't know for several weeks.

    A "15k oil filter" is a commercial filter that's guarenteed for 15,000 mile interval replacement. Supposedly it's of a higher quality than regular filters designed to be replaced every 5k or 10k. I use Fram Ultraguard, and from checking forums online, I feel the quality is reliable. I'm not the kind of person who saws his filter in half and compares it at X, Y, and Z mileage, then microscopically inspects the filter paper, and sends my oil out for analysis....but such people exist and I read their reports on it. I, personally, purchase the higher quality filters (even though I do 10k oil changes) because I have a higher mileage car, and I do a lot of highway driving so I want to put in a better filter. The difference in price is only about a dollar or two, so if it makes not actual difference, it doesn't hurt me.
     
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  8. bisco

    bisco cookie crumbler

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    perhaps damage was done in the first 70,000 miles.
     
  9. edthefox5

    edthefox5 Senior Member

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    Whats removing and cleaning the oil pressure switch going to do? It looks like its leaking where its attached. You need to get it on a lift and have a mechanic check it. May be leaking from the timing cover there have been a few of those reported.

    You have alot of corrosion on the crank pulley which makes me think the undercarriage should be checked too. Have a mechanic inspect the whole undercarriage after the engine.

    And clean all the leaf debris from the windshield water dam. if you clog those 2 front dam water vents there a pain to get clean. If they clog up the water will pour into the engine compartment.

    Check the oil every Saturday before you start the car. Every Saturday. Don't check it at the gas station as it takes a long time for all the oil to drain back to the pan with a VVT engine and will always look a little low. Don't bother with after market oil filters.Go to the dealer and buy the oem cartridge. There guaranteed to be correct and superior to anything you can buy. Modern cars and synthetic oil run pretty clean there's not alot to filter.
     
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  10. DrTrivia

    DrTrivia Member

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    UPDATE: I forget to do this at my last oil change, so sorry for the long wait. I did my last oil change at 140k. I added a half quart at 145k and was another half quart low for the oil change (based on the dipstick). I got an inspection camera to check the area. While there was oil on the Oil Pressure Switch, there was also oil higher up on the engine. I wasn't able to get a good picture of it, but I found another people who had the same issue in a different post (they posted no resolution). While it's not a bad idea to take it to a mechanic at this point, I have never found one that I trust. Loooong list of mechanics from both small garages, large chains, and dealships doing shoddy work or trying to screw me. Recent problem with a Hyundai dealership left me with a $600 bill because they broke something while working on it and I had to fix it myself. Ideally, I'd like to continue investigating this myself. For the time being, I cleaned the area and will monitor it to see if the oil buildup returns. Maybe it will help me narrow down where the problem is coming from. That's all for now.
     
  11. MeGuinness

    MeGuinness Member

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    My 2010 205k on the clock, 4.5L fresh oil in + new oil filter.....
    6k later the warning light of low oil comes up everytime I take a right corner....I did have to add 2.5l to reach top oil level...
    At 9k I decided to do the regular change of oil, about 2 litres only came out ,.

    Ps . I see oil all the time under the throttle body inside the intake manifold,I may try changing the pcv valve ??
    Crazy.

    Nexus 5X using PriusChat mobile app
     
  12. edthefox5

    edthefox5 Senior Member

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    Oil puddle in the intake is normal. Move along.
     
  13. Rebound

    Rebound Senior Member

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    All Gen III Prius' will have this oil puddle and replacing the PCV won't fix it. Only installing an oil catch can will fix it.
     
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  14. edthefox5

    edthefox5 Senior Member

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