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low oil in 2006 with n85,000 miles

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Paul R. Haller, Sep 5, 2013.

  1. Paul R. Haller

    Paul R. Haller Member

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    I have a 2006 that I maintain carefully. I've owned the car since new and change the oil and filter every 5000 miles with 05/30 Penzoil synthetic. It has never needed oil between oil and filter changes. I have always, prior to the last oil change, used Toyota filters. I started smelling a burnt plastic smell in my car and even my wife commented on the smell. It is approaching my 85,000 mile oil change and I decided to look things over because the Prius has no info on the display like oil pressure, water temp, etc.

    I was shocked to find that the oil was off the stick. It was low about 2 quarts! I added the oil and got under the car. There is no leaking oil anywhere, everything looks great. I checked and the oil was changed 4600 miles ago. All is the same except that last oil change instead of using a Toyota filter I used a Bosch filter. Is the Bosch filter somehow responsible for the 2 quart oil drop in 4800 miles? I just can't figure why such a huge disparity between this oil change and others. Any ideas?
    -Paul R. Haller-
     
    #1 Paul R. Haller, Sep 5, 2013
  2. bisco

    bisco cookie crumbler

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    'someone' didn't add enough oil at the last change.;)
     
    #2 bisco, Sep 5, 2013
  3. Patrick Wong

    Patrick Wong DIY Enthusiast

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    ...or a valve stem seal decided to start leaking. I doubt that the filter had anything to do with the oil consumption rate.
     
    #3 Patrick Wong, Sep 5, 2013
  4. uart

    uart Senior Member

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    Hi Paul, I know I'm going to sound like a bit of a dick for saying this, but I think it needs to be said.

    If you've got a car heading up towards 100k miles and 8 years old, and you never check the dipstick between changes, then honestly I think it's debatable that you maintain it carefully. Regularly checking the oil is possible the single most important piece of maintenance that you can do on any car.
     
    #4 uart, Sep 6, 2013
    PriusGuy32, 04prius123, Britprius and 1 other person like this.
  5. Paul R. Haller

    Paul R. Haller Member

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    Well, OK, fair enough, but I have been lulled into never checking because prior to now it's never needed a drop and I used to check each fill up so, the question still remains... Why now and not in a small amount but 2 quarts low? I do not see any smoke, where else is it going? You may not believe this but I did put in 3 and 1/2 quarts because I always buy the 5+ quart synthetic special at Pep boys and save the oil not used. In this case, they did not have the jug so, I bought the individual quarts and saved the rest. I had exactly 1 and 1/2 quarts left over.
    -Paul R. Haller-
     
    #5 Paul R. Haller, Sep 7, 2013
  6. SteveLee

    SteveLee Active Member

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    I'm with bisco, the most obvious answer is someone didn't put the amount in they were supposed to, unless you checked it soon after the oil change.
     
    #6 SteveLee, Sep 7, 2013
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

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    OK, if you are sure that 3.5 quarts had been put in, then my reply to your question is that at some point, a mechanical device will show wear. So if not now, it would happen at some point in the future.

    Consumption of 2 quarts over 4.6K miles is not a lot of oil and will not show up as visible smoke in the exhaust. Some auto manufacturers in the past have claimed that oil consumption of as much as 1 quart per 1K miles is acceptable for warranty purposes - which just shows that those manufacturers were not eager to perform major engine work under warranty...

    The oil may be leaking through the valve stem seals or may be leaking through the piston rings. If you care to find out, you would need to have a cylinder leakdown test performed to see whether the piston rings have a fault and if so which cylinders are having a problem. That test would also show whether the engine valves are sealing properly when closed.

    If the cylinder leakdown shows that all cylinders have good compression then it is likely that the oil consumption is due to the valve stem seals. If you care to do something about that, then the cylinder head would have to be removed so that the seals can be replaced.

    In any event, now that you know your car's engine will consume oil, I would encourage you to monitor the dipstick level periodically, like once a month or so, to see whether the oil consumption rate accelerates over time.
     
    #7 Patrick Wong, Sep 7, 2013
  8. bisco

    bisco cookie crumbler

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    i confess to never checking my oil either. and for the same reason, it never consumes any.:oops:
     
    #8 bisco, Sep 7, 2013
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