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serious drop in MPG. 20-22 MPG

Discussion in 'Gen 3 Prius Fuel Economy' started by bret kraupie, Feb 6, 2021.

  1. bret kraupie

    bret kraupie New Member

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    My 2011 when bought was getting ave. mpg 50+-. Moved from Seattle to San Diego and ave. 60-62 mpg going down. Coming back only got low to mid 40's. Its been a year since but it has slowing dropped to the mid 30's. and last week I noticed only 21-23 mpg. Yikes. I have noticed when I start driving while car is cold the mpg indicator does not jump up to 100 plus like normal. is stay 20-50 and after I drive for a bit it works correctly. I have 120,000k on car. I'm going to fill up and manually and see
    what my mileage is on next fill-up. Also was going to change spark plugs. Any other info. Thanks.....
     
  2. Paul E. Highway

    Paul E. Highway Active Member

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  3. bisco

    bisco cookie crumbler

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    welcome!

    clean the egr circuit before you blow a gasket, if you haven't already

    with 120k, i would do a major service as well
     
  4. bret kraupie

    bret kraupie New Member

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    I tried top find my battery reciept
    Ya Ill check it out. I put a new one in the car about three years ago, but maybe it is failing. I put new spark plugs in yesterday. It seems to be better(not totally). Thanks
     
  5. bret kraupie

    bret kraupie New Member

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    I checked the battery out and it is fine....

    can you tell me what egr stands for thanks.
     
    #5 bret kraupie, Mar 2, 2021
    Last edited by a moderator: Mar 2, 2021
  6. bret kraupie

    bret kraupie New Member

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    Ya the battery is fine..
     
    #6 bret kraupie, Mar 2, 2021
    Last edited by a moderator: Mar 2, 2021
  7. bret kraupie

    bret kraupie New Member

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    Thanks. Ill check the EGR. Are you talking about the tube that goes to the manifold. and I assume check both the ends that the tube hooks to.
     
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  8. bisco

    bisco cookie crumbler

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  9. fuzzy1

    fuzzy1 Senior Member

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    What is the typical trip length now? If under 2 miles, that might be reasonable. But if much longer, then not so good.
    The EGR cooler, a heat exchanger that is plumbed into the engine cooling system, is a particularly bad clog point.
     
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  10. Grit

    Grit Senior Member

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    what type of meter did you use that displayed “fine” in metric units?
     
  11. bret kraupie

    bret kraupie New Member

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    Not sure. I had Napa auto parts, and O rileys auto parts checked for me. They both said it was good.
     
  12. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Exhaust Gas Recirculation. More info:

    Bad Flywheel | PriusChat
     
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  13. Rick2015Prius

    Rick2015Prius Junior Member

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    Hmmm, how did you come out?

    I have a 2015 that is all of a sudden getting 20. It has 116k and has been sitting a lot this past year. I also recently took it to Toyota for a software recall update but not sure that is the issue.

    It is ready for a major service. I’ve only changed oil, couple sets of tires, the trans fluid and replaced the headlight and marker bulbs a few times . It’s a recall on earlier years but not 2015, again I can’t complain though, I love the car, black/black w leather, nav, moonroof and solar ❤️

    Back to it. I need to change plugs, is it an easy access job? Also noticing people mentioning egr and maf, are they easy access jobs? I’d prefer to replace myself. I have a good set of tools and while it’s been years since I’ve wrenched much, I’m up for it. What else would ppl recommend for the best maint on a g3 with 116k. Also bear in mind that I have a 4x6 utility trailer that I occasionally haul stuff around with, so I am cognizant that it gets a little extra exercise from the occasional pull.

    Kk, thanks in advance for the advise.
     
  14. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    For Exhaust Gas Recirculation cleaning see my link (post above yours).
     
  15. Grit

    Grit Senior Member

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    SPAM link! it’s listed as “bad flywheel.”
     
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  16. Norryboy1a

    Norryboy1a Junior Member

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    I’ve noticed a lot better mileage after changing the engine air intake filter.
     
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  17. Grit

    Grit Senior Member

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    which brand?
     
  18. fuzzy1

    fuzzy1 Senior Member

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    Shouldn't a clogged air filter be causing a significant loss of power before it has any noticeable impact on MPG?
     
  19. Norryboy1a

    Norryboy1a Junior Member

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    no
     
  20. Norryboy1a

    Norryboy1a Junior Member

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    I think it was a fram