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Crankshaft position sensor wetted with oil

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by HermG, Jan 7, 2013.

  1. HermG

    HermG New Member

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    I noticed dime sized oil spots appearing on garage floor about a month ago, a couple of weeks after a dealer oil change (the oil level is at the max mark). These were on the passenger side, about a foot inboard of the wheel. Because they were increasing and could not be attributed to another vehicle, I began to poke around. I found a sensor aft and slightly above the crank pulley covered with oil, with no sign of an oil leak above it. There was oil on the suspension parts below the sensor. It is the only sensor/wire visable in this area. Could this leak be something as simple as a defective O-ring? Could a new sensor be installed easily without all the diagnostic and labor charges that come from a dealer? There are no warning lights, the vehicle starts/idles/runs normally. Has anybody else had this problem; what did you do?
     
    #1 HermG, Jan 7, 2013
  2. spiderman

    spiderman wretched

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    How many miles on the clock?
     
    #2 spiderman, Jan 7, 2013
  3. HermG

    HermG New Member

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    42,000+ (since 9/09).
     
    #3 HermG, Jan 7, 2013
  4. spiderman

    spiderman wretched

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    Hmm, did you check with the dealership to see if by chance they may cover it? Likely covered under the 3/36K but you never know.

    Welcome aboard by the way!
     
    #4 spiderman, Jan 7, 2013
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  5. ursle

    ursle Gas miser

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    The gen3 has a funny oil filter attachment scheme, might be worth looking at it to see if it's the culprit, even the bolt that releases the oil could be leaking, at speed with wind the fluids going to move, a polite talk with the service manager should set your mind at ease, they already have your money and they want more, shouldn't be a problem.
     
    #5 ursle, Jan 7, 2013
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  6. priusbee

    priusbee Member

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    Do you have a picture of that? It is hard to diagnose without seeing. Give us a big picture pointing where the leak is at will help.

    Thanks!
     
    #6 priusbee, Jan 8, 2013
  7. priusbee

    priusbee Member

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    If you have a wet oil spot, usually there is a sealing issue. Either the seal is warped or other problem.
     
    #7 priusbee, Jan 8, 2013
  8. HermG

    HermG New Member

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    132-3275_IMG.JPG 132-3275_IMG.JPG 132-3276_IMG.JPG
     
    #8 HermG, Jan 8, 2013
  9. priusbee

    priusbee Member

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    If it is the sensor, you are in luck.
    More Information for BECK/ARNLEY 1800713

    Notice that the seal, you maybe able to replace the seal.
    Looking at the picture, I believe it is only 1 bolt holding it down.
    If you are handy, you can try to take the sensor out. I am not sure you have to drain the oil or not since I cannot see the picture clearly.

    If it is the crankshaft, here are the pictures of the crank seals.
    front seal: More Information for TIMKEN 223802
    Rear seal: More Information for NATIONAL 223801

    If you look at the picture of the crank seals, it is a circular seal, meaning you have to remove the engine to do the replacement of the seal. The front, you maybe able to remove the timing cover. Labor intensive.
    I know Toyota build a sturdy engine and crank seals unlikely at 40K miles.
     
    #9 priusbee, Jan 8, 2013
  10. HermG

    HermG New Member

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    What I thought was the crankshaft position sensor in the above pictures was actually the oil pressure switch. It had developed a small leak in the switch body, and not the threads were it screws into the block. This is not a common failure. The switch failure was diagnosed and repaired by Power/Cerritos Toyota under warranty. I'm a happy camper on this one!
     
    #10 HermG, Jan 10, 2013
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  11. priusbee

    priusbee Member

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    Oil Power Switch sensor is known for that - I had that happen to my car made by Nissan. It is good that you pay attention and the car is still under warranty. The only loss is that you spent some time to have it repair.
     
    #11 priusbee, Jan 10, 2013
  12. BardManY2k

    BardManY2k Junior Member

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    I am having the same problem as OP, I believe. After a ton of searching I landed on this thread - glad OP got it taken care of under warranty. Our 2010 has about 80,000 miles at this point and has been trouble-free so far. I haven't seen any leaks on the garage floor yet, but did notice the oil level was a bit low over the last few thousand miles. I added about a half quart. Getting oil change on Wednesday and will monitor very closely for oil consumption.

    I do all of the maintenance myself on other cars, but I usually let dealer do Prius. I did do transaxle fluid on Prius recently, also cabin/engine air filters, etc. I may just start doing my own oil changes too, but that is a whole different thread.

    In any case, I've attached a few photos and would appreciate any information/confirmation that it is indeed the oil pressure sensor I'm looking at.

    Thanks,
    Brad

    Wide view:
    [​IMG]


    Closeup:
    [​IMG]
     
    #12 BardManY2k, Feb 9, 2014
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