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How do I increase the MPG on my 2009 Prius?

Discussion in 'Gen 2 Prius Fuel Economy' started by Joe Wall, Jan 20, 2019.

  1. Joe Wall

    Joe Wall Member

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    I drove my Prius on the highway about 800 miles and went up to 37.9 MPG, but it is winter at like 19 degrees and getting below zero some days. It is advertised it gets about 45 to 48 and is a 2009 Toyota (Touring) Prius. I realize in the summer it will do better. Any advice for me? I was really hoping to do better on PMG.
     
  2. mpg_numbers_guy

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    Check your tire pressure. Tires wear better and provide better fuel economy at sidewall max. Some choose to go above sidewall max for even better fuel economy, but that is at your own discretion.

    0-30F temps in Michigan. My mom averages 44-48 MPG in the winter on newer winter tires at the sidewall max of 50 PSI. I generally top 50 MPG in the winter, but that's with hypermiling.

    Maintenance, spark plugs, not going faster than 65 MPH, etc. all benefit fuel economy. I've read on the 3rd gen that 50 MPH - 65 MPH keeps the engine running at it's peak fuel efficiency, and that 40-45 MPH is best for overall economy. I'd surmise that the 2nd gen is similar.

    EPA tests are done in the summer. Hybrids take a bigger MPG hit in the winter. My Insight gets 70 MPG in the winter and is probably losing 20 MPG due to the temperatures. I'd surmise the Prius is similar percentagewise.
     
  3. KK6PD

    KK6PD _ . _ . / _ _ . _

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    I had a 08 Gen II for 9 years, I found, do not drive over 65 on the freeway.... take city streets whenever possible, VERY IMPORTANT ...learn how to hypermile, , AND YES WINTER WILL KILL YOUR MILEAGE! I was getting 44mpg while I owned it, and without following these rules, I would have been in the mid 30's!!!
    Good Luck on this one!!!
     
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  4. bisco

    bisco cookie crumbler

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    it was advertised in 2009 as getting 48 mpg. 10 years later, and how many miles? toyota likely wouldn't make the claim.
    there are so many things that affect mpg. tires, batteries, filters, oil, injectors, throttle body, sensors, suspension, injectors, piston rings, spark plugs, the list goes on.

    start with the gen 2 'prius fuel economy' sticky threads
     
  5. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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  6. PAUL SCHULTZ

    PAUL SCHULTZ Member

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    I've had my 2008 Touring for 12 months. In the Michigan, driving 60/40 expressway/city and not hypermiling but driving with traffic... about 70-75 mph on the expressway I am getting 38-40 mpg in winter, 43-45 mpg in summer. I have my tires at 38 psi. I don't run them higher since it makes for a rougher ride.

    I accept these numbers and know I could do better with changing my techniques. But, I dont' want to... or need to. I mainly give my stats to illustrate the difference between winter and summer numbers. It is about 5 mpg. So, if you drive similar to me then in my mind your fuel economy is not far off.

    Paul
     
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  7. PAUL SCHULTZ

    PAUL SCHULTZ Member

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    Here is a link to the fuelly page for the gen 2 Prius. Take a look at the average mpg, it is about 42-44mpg. Some of these are driven in warm climates only. Some in the snow belt. But, using the 5 mpg swing I noted above this avg covers what I have been seeing in my first 12 months of ownership.

    Toyota Prius MPG - Actual MPG from 1,558 Toyota Prius owners

    Paul
     
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  8. VFerdman

    VFerdman Senior Member

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    It's all about the average, not instant MPG. Average your fuel consumption over a year of driving and then re-post with questions. Cold weather causes Prius to use more fuel. Just think, if you have your cabin temperature set to 70 degrees F and it's 10 degrees F outside, you are asking for 60 degree F differential from your heater. In the summer when it's 100 Degrees F and you have your cabin set to 70 you are only asking for 30 degrees F differential.

    Even if you turn off your heater in the winter (crazy!), the ICE needs to keep itself warm in order to operate properly and economically, so it will just come on to keep the coolant warm sometimes. It's the way of the Prius, you can't do much about it. All the suggestions above are valid, but they will not add up to much. Warmer outside temps will do a lot more towards your fuel economy. So don't worry about it, turn off the big screen and enjoy driving the car. It will most likely average out to about 45 MPG over a year, which is great.
     
  9. PAUL SCHULTZ

    PAUL SCHULTZ Member

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    upload_2019-1-21_12-3-46.png

    This is my montly fuel-up averages for the past year in my 2008 Touring. It shows the change due to the cold midwestern weather.

    Paul.
     
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  10. VFerdman

    VFerdman Senior Member

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    Two of the largest factors I noticed in my Gen 2's fuel consumption are

    1. Outside temperature
    2. Driving at highway speeds

    Those two are way more significant than any of the other common Prius factors. I can try and hypermile, pump up my tires to 40psi, etc., but all I get is maybe 5% from all my efforts. Outside temperature drops from 60's F to 30's F and I loose 10%-15% just like that.

    I drive on the highway quite a bit with this car and I usually go no slower than 73mph, sometimes a lot faster. That usually costs me around 5%-10% hit on the economy.

    Given all that I still average 45mpg year round. It may have fallen a bit this past year as I have gotten a bit worse about highway driving. Still, 5%-10% on a 45mpg car is not a lot and I am still burning less fuel per mile than the vast majority of people. It's all about how much effort one is willing to put per unit of reward (mpg). As a new Prius owner I first tried all the techniques and was very much into squeezing all I could from the Prius in terms of fuel economy. I think it's normal and commendable. After a year and half and over 25K miles, however I have come to realization that "just driving" this car is the best possible solution for me. All the "special" efforts for squeezing the Prius may net 5% at best and nothing at worst. This is what I found through my experience and now I am very happy driving more or less normal with some things I have learned during the "novelty" stage kind of burned into my muscle memory. I use the brakes gently, I try to use the features of terrain I am on to my advantage, etc. My economy has dropped a tiny bit from last year, but I am still at 45mpg since I bought the car in July 2017. I'll take that and enjoy it. I love this car for its ability to just be driven and still providing great fuel economy.
     
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  11. sam spade 2

    sam spade 2 Senior Member

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    Not quite true. It is ESTIMATED that it can get mileage that high.
    It is not unusual, with any car, to not be able to reach that number in real world driving.

    The max. gas mileage is usually obtained around 50 MPH on flat ground.
    Faster than that, it goes down.
    A lot of stops and starts, it goes down.

    Your driving situation and habits have a LOT to do with it.
     
  12. Aztechmaster

    Aztechmaster Member

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    My commute is 38 miles one way in the Black Hills of SD. Yes up and down big long hills
    The weather here is cold and damp, usually 8 to 30 degrees. Right now I am averaging 41.8 ish warmer days it tops 42. Summer here I get 44 to 46. Not bad for a 13 year old car with 250K miles.

    Posted via the PriusChat mobile app.
     
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  13. Joe Wall

    Joe Wall Member

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    Anyone use pulse and glide? I was accelerating to speed then putting foot on gas and off, on and off. It seemed like I could get up over 50 MPG on some intervals. Is pulse and glide just accelerating and maintaining a constant speed?
     
  14. bisco

    bisco cookie crumbler

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    i do, works great

    i accelerate moderately to speed or 5mph higher (pulse), release the pedal then slowly press it until the arrows disappear between the engine, battery and wheels (glide)

    when i'm down to the speed limit or below (depending on traffic) i repeat.
     
  15. dolj

    dolj Senior Member

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    I do, and pretty much as bisco described it. It sounds like you might be missing the crucial press the accelerator until there are no arrow bit. If you don't do that you will slow too quickly. Just keep doing it until it becomes habit.

    I think pulse & glide is the single most important technique to master if it is high MPGs you're after.
     
  16. Joe Wall

    Joe Wall Member

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    I don't see any arrows at all. How long do you slowly press pedal?

    Also any precautionary tips as I'll be traveling 13 hours in frigid conditions (-20 to -50 below zero) from Wisconsin.
     
  17. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    This may be time to focus on safety, not some little screen looking for arrows. That cold, I would consider getting gas at 3 pips, no way you want to run out.
     
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  18. dolj

    dolj Senior Member

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    On the Gen 2, the energy flow arrows are on the Energy Monitor screen and I have numbered them 1, 2, 3 and 4 in the image below.
    Prius MDF Energy arrows.jpg

    When you have the accelerator backed right off, the arrows 2 & 4 are green (pointing towards the battery). After backing off the accelerator, the best technique is quickly apply just a little pressure and wait 1 second (as the screen refresh rate is quite slow 500 ms to 1 sec). You're looking for arrows 1, 3 & 4 to look like arrow 2 above. If the arrows remain green press a little more and hold again. Repeat until you see no arrows. If you get arrows as shown above or, in addition, arrows 3 & 4 turn pink (and point towards the wheels), then you have gone too far and you need to back off (and hold) a fraction.

    It takes a little practice in the beginning, but you quickly develop a muscle memory and can more or less adjust the pedal to get to the right range, without reference to the screen. I mostly do a quick glance to confirm nowadays as I pretty much know where the glide range is by feel.

    In addition to that, in such cold weather, you will likely not be able to get any useful gliding. There just won't likely be any surplus energy to capture. It will be going towards making heat for the cabin or pushing against the added friction due to winter conditions. So leave it for the better weather to get trained up.
     
    #18 dolj, Jan 29, 2019
    Last edited: Jan 29, 2019
  19. sam spade 2

    sam spade 2 Senior Member

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    And I think that traveling AT ALL in those temperatures is ...mmmmm......not wise.
    Even the Post Office has suspended delivery in some states.

    AND.....under those conditions, there are a LOT of things to worry about before trying to eek out a couple of extra miles per gallon, like just keeping the engine running enough to keep it from freezing up solid since the coolant mix might not be able to handle those temps.
     
  20. willakwin

    willakwin New Member

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    My commute is 38 miles one way in the Black Hills of SD.