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New 2015 prius v (lowercase v for the Prius v wagon) mpg concern

Discussion in 'Prius v Fuel Economy' started by ultravorx, Sep 28, 2015.

  1. fuzzy1

    fuzzy1 Senior Member

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    Mileage always gets worse in winter due to winter fuel blends (lower energy density), lower temperatures, falling tire pressure (if you haven't topped off), water on the roads, and cabin heat. Here is a thread about it:
    Why mileage gets worse in winter | PriusChat


    As for your baseline mpg, there are many things that could be holding it down, including driving style, particular driving route, and traffic conditions. I don't see anywhere near enough clues in the thread above to point us in the right direction, so please fill out as much of this questionnaire as practical and post the answers here:
    Fuel economy complaints/queries? Please copy, paste & answer these questions, esp. if you're new | PriusChat
     
  2. ultravorx

    ultravorx Junior Member

    Joined:
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    Pa
    Vehicle:
    2016 Prius
    Model:
    Three Touring
    What fuel economy are you getting and how are you determining fuel economy? (trip computer or manual calculations)
    Im using hand calculations
    - What fuel economy are you expecting and why?
    I was expecting low to mid 40's with 80 city driving and 20 highway
    - What are the approximate outside air temps?
    its been ranging 30-50F
    - How long are your trips?
    Typical commute to work is approx 8 miles
    How old is your 12v battery? What is the voltage reading of your 12v battery after sitting over night? (Method Here)
    The car is a 2015, so brand new
    Have you had your alignment checked? Any pulling or abnormal tire wear?
    No pulling, but car is brand new
    - How much of it is city vs. highway? Roughly what's the average speed in overall and and of each segment? Is there a lot of stop and go driving?
    80 city driving and 20 highway City is avg 30-40, with constant driving
    - What's the terrain like of your drives? (e.g. flat, gentle hills, steep hills, etc.)
    flat to small hills
    - What are your tire pressures?
    35psi
    - Is your oil overfilled? (i.e. above the full mark on the dipstick)
    oil is at top of hatch marks
    - Make, model, year, engine and transmission of previous car? (e.g. 08 Honda Civic Si 2.0L 4 cylinder, manual transmission) What did you actually get on the same trips/commute? (Please give us actual numbers, not EPA ratings.)
    2010 nissan armada, 5.7 v8 auto. Same trip yielded 13mpg (lol)
    - What region/state are you in? (if you haven't set your location)
    CT
    - How are you trying to drive (e.g. trying to stay in electric only?) and how hard are you braking?
    Easy acceleration and light braking, Usually score 80-90 on the dash chart
    - What modes are you using, if any? "normal", EV, power, eco?
    Normal
    - Are you "warming up" the ICE (internal combustion engine) by letting it idle after powering on?
    Just in the AM, since its been in the 30's using a remote start
    - Are you driving using D or B mode?
    Use only D
    - HVAC settings? Are you using the heater, AC, auto mode, etc.? If using auto, what temp is it set to?
    Auto set to 70
    - Are you using the factory tires and wheels? If not, please indicate tire make, model and size (e.g. Goodyear Assurance Fuel Max 185/65R15).
    Factory 17" tires
    - If reporting a mileage drop, did anything significant change on your car (e.g. accident, hit a curb or big pothole throwing off alignment, oil change/other maintenance/repairs, changed tires or wheels, etc.) or your commute?
    difference is a temp drop
     
  3. bisco

    bisco cookie crumbler

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    Plug-in Base
    hey! who violated my post?:eek:
     
  4. bisco

    bisco cookie crumbler

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    try eco mode on a tank and see what happens. what is the epa mpg rating?
     
  5. fuzzy1

    fuzzy1 Senior Member

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    Re-ordered a bit --
    The wider 17" tires produce lower MPG than the 15" ones, but the EPA does not force a separate rating. The sticker is a weighted average of the sales mix, with is heavily dominated by the 15" version.

    Many of us push pressures higher for better MPG, but your 17"ers cannot take as much extra before producing a too harsh ride.
    That outside temperature alone hurts engine efficiency. (Grill blocking in winter can help this.) The cabin heat then sucks more heat out of the engine, which must be replaced by a bit of fuel burn. Auto Set at 70 then sucks more heat out of the engine than a fixed fan setting of lower temperature. And using remote start to warm the cabin before you step in, means that much of this heat comes from an initial fuel burn, not from 'waste' heat during the driving cycle.

    This becomes a trade-off between MPG and human comfort (and possibly safety, if the windows need heat to maintain visibility). If you want winter comfort, just be aware that it costs extra fuel. MPG should improve significantly when warm spring weather arrives, peaking the day before air conditioning season arrives.

    It may also be useful to reset one of the trip meters both morning and evening, and see how much MPG difference appears between mornings with remote warmup, and evenings without warmup. But the differing outside temperatures will complicate the comparison.

    Dry roads produce the best MPG. The more water that the tires have to push aside, especially at highway speed, the lower the MPG.
    Short trips produce lower MPG than long trips, because the substantial warmup fuel penalty is amortized over fewer miles. Your commute is a medium distance, so MPG ought to be neither the best nor worst.
     
    ultravorx likes this.
  6. Hboggs

    Hboggs Junior Member

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    Adel, Ga
    Vehicle:
    2015 Prius v wagon
    Model:
    IV
    Hi. I've been away for a while as we had traded our Prius II for a Sienna Van which has now been traded for a 2015 Prius V. I have keep very detailed records on all my vehicles and I've noticed the following: (1) The mileage will improve as you put more miles on the car; (2) the car computer MPG is usually on the average 5% higher than actual calculated MPG. That being said, let me make a suggestion. Try to purchase your fuel as much as possible at the same station and even use the same pump if possible. Find a station that has a large sales volume as that will tend to give you a better fuel quality. Now I'm trying something new with our 2015 V. We have a local station that sells 100% no ethanol gas and I've used that for our first two fill-ups and I plan on using it as much as possible. As long as we are not on a trip this will not be a problem. I will use 90/10 when necessary. My previous experience showed about a 2 mpg increase (Honda Fit) over 45000 miles with 1/2 being 100% and 1/2 being 90/10. It is my opinion that over the life of the vehicle, the 100% fuel is better for the fuel system. In our area every yard maintenance service uses 100% as the 90/10 causes problems with their equipment. Granted a car is different, but I still think there is a positive affect. I don't think that the additional co$t is offset by any fuel increase, but that is not my main concern.
     
    #26 Hboggs, Dec 16, 2015
    Last edited: Dec 18, 2015
    schmuly likes this.