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20% improvement in MPG

Discussion in 'Gen 2 Prius Fuel Economy' started by *Goldfinger*, Mar 4, 2014.

  1. Jason in OZ

    Jason in OZ Active Member

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    Location:
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    2006 Prius
    yes, i have a plug in system installed in the Prius.
    it started life as an enginer kit, and i recently rebuilt it using better batteries and decent charger and Battery Management System. the enginer type PHEV is basically an on board charger for the HV battery.

    basically if my trip is less than about 1hr 15 mins or so, the HV battery will almost never drop below 7 Green bars.
    because it's at a MUCH higher charge than it would usually be, i can use EV and Warp stealth mode much more often.
    that's the only reason i am able to get such good numbers.

    this week so far, im actually BETTER than last tank. currently averaging 2.0L per 100km (in the first 150km or so of the new tank) that's 117MPG us. pretty incredible.

    here's a link to the thread where i rebuilt the system.

    Enginer PHEV kit Rebuilt with quality components and new batteries | PriusChat

    Jason.
     
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  2. uart

    uart Senior Member

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  3. HaroldW

    HaroldW Active Member

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    Three
    I just filled my tank with 800 kilometer and my tank took 36.48 Ltr.. 4.3 per 100. I did not check my average speed but probably around 80 kph, Jason . My Prius is a stock 2014 G 3. Fairly cool temperatures here yet 10 - 20 C. and all short mileage trips.H
     
  4. Jason in OZ

    Jason in OZ Active Member

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    very good numbers indeed.

    I'm taking a trip to Brisbane from Sydney in June, about 1000km each way and almost all of it will be in 100-110kmh zones so the PHEV system will contribute very little, as once above about 70kmh, the ICE runs most of the time anyway, so im kind of curious to see what kind of economy i will get.

    the PHEV kit will be turned off once i get on the Freeways and Highways (to save battery).

    i will report back once that trip happens.
     
  5. Scallywag

    Scallywag Member

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    I recently had my 12V unplugged, and then drove about 360 miles at 75+ mph (mostly cruise control) for a 48mpg average. That's the best I've done yet at such speeds. Wondering if there's something to this computer reset thing?

    I didn't charge the 12V at all while it was unplugged.
     
  6. uart

    uart Senior Member

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    My take on this is that the MPG display is not necessarily the most accurate for some time after a 12V disconnect (ECU reset).

    From what I've read the Prius collects "historical data" which helps it to calibrate the measured fuel flow rate (which basically comes from just summing up injector pulse widths). When this data is reset the fuel rate calculations revert to default parameters, which may either underestimate or over estimate the fuel flow somewhat. Over time these parameters get fine tuned and the fuel calculations become more refined.

    The bottom line is that some people will get MPG numbers that are overestimates and others will get underestimates after a 12V reset. We see post after post here of people getting their Prius back after a routine service and complaining loudly about mysterious loss of MPG. Almost invariably they return to normal without intervention after a month or two.
     
  7. CatsAreGods

    CatsAreGods Junior Member

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    That's why the best way to measure consumption is to track distance and divide by quantity of fuel used. If it matches the computer, fine, but I use the computer to tell me trends, not actual data.

    Nexus 4 ?