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Recall vs Loss of MPG?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by thomas goddard, May 16, 2014.

  1. thomas goddard

    thomas goddard Junior Member

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    Had the ECU recall done last week, I have now lost 10 yes 10 mpg (down to 40.6 and dropping) and the only change done was the recall for the flashing of the ECU!!!!!!!!!!! Anyone have this experience? This loss is in my city driving that has always been around 50.1-50.4 mpg. I haven't been on a trip yet (afraid I will lose even more!) I wonder if I disconnect the 12 volt starting battery if the ECU will re-think and snap out of the dilemma it is in, any ideas would be appreciated, thanks
     
  2. armyvet282

    armyvet282 Junior Member

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    Jesus Christ!! :eek: If the ECU update is what has caused this for you, then I'm not doing mine anytime soon!

    In all reality, I don't even know if that recall is all that necessary. Apparently, nothing serious ever happened because of it, and the potential for any damage to the car is rather slim, even if you drive like there's no tomorrow.

    I had a 2010 Prius before, and let's just say some people (not me) have driven it with a lead foot. After all that abuse, it still ran like a champ, so obviously even them stomping the gas pedal didn't fry the transistors.

    Anyway, I hope your MPGs go back up! Disconnecting the 12v battery sounds like a good place to start, but then again I'm no expert. :) Good luck!
     
  3. kbeck

    kbeck Active Member

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    Interesting. There's been a bunch of us here who have had the update, including me. It's a hard call, but I might have seen an MPG drop in the low single digits.. And that's iffy, since the car gets its best when its warm out.

    Most others who have reported on the issue have reported a slight loss; others have reported a slight gain; and several have reported a slight change in the driving characteristics. But, to my knowledge, Mr. Goddard here is the first to report such a dramatic change.

    Mr. Goddard, if you really are having that big a drop in the MGP, take it back to Toyota. I'm still getting in the low 50's (indicated)/high 40's (calculated); if you've got that big a drop, there's probably something busted.

    KBeck
     
  4. spiderman

    spiderman wretched

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    There have been more than one member teporting reduced fe. Enough to see a possible trend.
     
  5. xliderider

    xliderider Senior Member

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    It was reported that the software update involves two separate flashes of two different ecu units. Bad outcomes like the OP's resulted when the second flash was started/applied before receiving a message that the first flash was completed successfully.

    Take the car back to Toyota. I'm not sure if the ecu units can be reflashed or not, or if it's FUBAR and will need to be replaced.
     
  6. bisco

    bisco cookie crumbler

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    how many tanks have you driven since the recall? i don't think resetting is going to change anything.
     
  7. thomas goddard

    thomas goddard Junior Member

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    I've got an appointment at the Toyota dealer that did the recall on May 20th, good to know that there are 2 flashes that need to be done. I wonder if the memory in the ECU will show that 2 flashes were done and completed?
     
  8. Spindifferent

    Spindifferent Member

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    No issues after the update for me.
     
  9. KennewickMan

    KennewickMan Junior Member

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    No issues after the update for me either, for those of you who are thinking about not the update should change you mind because the update in critical to the longengivity of the inverter. I had mind done & also had a Tanabe strut brace & it was hard to get to the fuse box if they need to remove a fuse as part of the upgrade. After the upgrade I put on four new Continental pure contact tires & the milage dropped by 2 miles per gal. that should get better after the tires brake in............... George
     
  10. Skunkworks

    Skunkworks Member

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    I lost 5 mpg.
     
  11. HaroldW

    HaroldW Active Member

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    No issues for me. Check your tire pressure. They may have dropped your pressures? I run 40 ft. and 38 aft. H
     
  12. LulzChicken

    LulzChicken Prius Enthusiast

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    I did the update and I have no issues with my MPG after. Maybe it's just a coincidence or something greater...
     
  13. MSA14

    MSA14 Junior Member

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    I have a new 2014 with the update already done before sale and I'm averaging 50mpg +
     
  14. wbray123

    wbray123 Junior Member

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    I had mine done a few months back and had an increase in mpg. However, I've read that there are multiple versions of software for the same Prius model years. It may result in improvement, decreased mileage or no change depending on what software you had to start with. At least that's my take on what I've read on the forum and the various reports of how it has had different effects for different owners.
     
  15. engerysaver

    engerysaver Real Senior Member

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    I agree with this; I have heard this happen before ..... And yes, take your Prius back to the dealer.
    Give us an up-date on your Prius, after they re-do their software flashes; or other fixes.
     
    snead_c likes this.
  16. thomas goddard

    thomas goddard Junior Member

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    Well, I have an increase in mileage now, 2 trips and computer generated mpg is at 56.1 which is about 8 mpg greater than prior to the recall install. I guess the computer had to re-think itself that is why the mileage dropped so much before it started back up in the mileage department. I'm afraid to take it back to the dealer, I'll just live with whatever mileage I get from now on!!!!! Thanks to all for there input.
     
    #16 thomas goddard, May 28, 2014
    Last edited: May 28, 2014
  17. Stratman

    Stratman Member

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    Same here. Averaging actual of about 52mpg on 6 or 7 total tanks on my 2014
     
  18. MikeDee

    MikeDee Senior Member

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    My first tank mpg after the recall wasn't good, but this second tank mpg is looking good.
     
  19. grin19

    grin19 Junior Member

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    I am on my 2nd tank since the recall. My city mileage has dropped from 45 mpg to 36 mpg. Is this normal? Will it correct itself? This is really disturbing.
     
  20. grin19

    grin19 Junior Member

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    See my post...mine has also dropped 10-12 mpg.