Help! My 2014 Prius v only 30 to 37 mpg

Damn. It was going pretty good........until you threw THAT into the mix.
There is absolutely NO evidence that there is "anything wrong".
You saying that just complicates the discussion at this point.

 

I agree...

See my last post... Lol.

I think the only thing "wrong" is driving habit (high speed, not using p&g, proper techniques), etc, high expectations, and improperly inflated tires...and that whole winter thing that's going on now....

 

i disagree. when the o/p finally stated that he was getting the same around town as 75 mph, that's when the thread took a u turn. post #31, perhaps you gentlemen missed it.

 

And I disagree as well. I did read that post, but it is entirely plausible that if the op is driving the prius v like a most people do in the city (like each traffic light is a race) with disregard for proper hybrid technics low 30 mpg's seem totally normal and in line with 75 mph highway mpg....and like I said add all the other variables (tires, cold, etc)...

Here is how I know why. When I owned my last prius three (2013) my average mpg was very high 40's, low 50's roughly. My wife took over driving that car and drove it full time for about 6 months or so. Guess what her mpg was after I checked it after those 6 months or so..... 38!!! This is on a 2013 liftback. When she took over driving it I tried a few times to teach her some techniques but it obviously didn't work, she was used to driving a normal car and drove the prius that was....

So a v that is significantly larger and heavier than a liftback being driven hard in the city with no hybrid techniques can very easily get low 30's mpg even at 40-50's temps...

 

well, it's certainly possible, but we just don't know, do we.

 

This is true. We do not. What we do know is op states she is not comfortable slowing down at all it seems on the highway... This might translate to city driving as well. Zoom zoom.

I'll tell you what though. When I checked trip B (which she knew not to reset) On my old car after my wife had it for that stretch I almost fainted. I didn't want to believe that all my hard work getting 50 +\- mpg was gone.... Oh well. So goes life..

 

And therefore "we" should NOT be saying "there is definitely something wrong".

 

For those that suggest his speeds are the culprit, I can't disagree more. Quite sure my area is far hillier, and when the temps are that warm, I have no problem staying in the 40-45 mpg range cruising at 70-75 on the interstate. Most of my highest mpg trip achievements have been at those speeds on long trips.

I would suggest the tire inflation as well. We're heading down to 10 to 20 below zero tonight, so I think I might need more air.

 

What, are you saying that speed is not a factor in gas mileage ? If so, you are just plain wrong.
And I think it is a "she".

 

well, it looks like we've got a nice little controversy on our hands. should be a fun day.

 

....and his fuelly profile is showing sub 40 mpg. Lol.

STEVEVEE, are you actually saying that you get better mpg on your interstate trips going 70+ mph as compared to the same trip at 55-60? I have to say impossible.

Anyways. Of course speed plays a huge factor in mpg, umm physics.

If I set cc to 65 on my work commute I average about mid 40's with my persona on a average day, if I set cc to 55 I average high 40's to mid 50's (barring the sub zero days)... This is per the post trip shut down screen on a daily basis, my lifetime avg is quite a bit lower of course re. Short trips n the such. And also my commute to work is always better that my commute home as I presume less elevation change on the way in plus driving home in the middle of the night = colder temps, this is a constant no matter how hard I try.

It takes more energy to push a vehicle faster. It is what it is.

I really enjoy the min by min screen to monitor mpg patterns..

 

Guess what I got for mpg today on my commute, it was a pitiful 38.2 per the after trip screen, my worst thus far I do believe. Cold weather sucks! My lifetime average on trip b actually went down .2 mpg which also sucks...

It was in the teens for temp. Coldest day yet around here, snowed a couple inches yesterday, and get this I was at 55 mph on cc on my highway stretch, and slow city traffic for the last bit. Heater set to auto at 69-70 after windshield thawed out.

I have a persona with the stock 17's at 44/42 psi, So yeah low 30's in a v with all the other issues we know exist (tire pressure, need for speed, etc) seems about right when pushing 75 mph, or driving it hard in the city with the heater going strong.

 

Gotta love generalizations. No I wasn't saying that at all. I was saying that given the temps he was in, those speeds are fine. If he has a heavy foot from 0 - whatever, yes, that eats gas, as it does in any car. I hardly ever use CC in this car, mileage suffers. I live in real hills, windy conditions, cold weather. My mileage is sub 40 now for various reasons.

I have a 80 mile commute when I do that trip, and it's along hills through mountains. I don't save much $$$ by driving 65 versus 70 or more. I need to be where I need to be. I also don't drive as much as I used to, this car has barely 17k on it since May 2013. I have documented long trips in warmer weather, from 45 degrees to 80. 75 highway all the way, mid 40's for mileage.

Today, temps dropped to zero and below, plus an intense 25 - 35 mph headwind. It was snowing, so the slower speeds helped me achieve 37 overall for this tank. Our Camry Hybrid has far less impacts due to cold and wind, some, but a lot less. I also had a 2004 Corolla for years, same trips. I almost always averaged 38, 75 always on the interstate.

Achieving "her" kind of mileage in relatively mild temps is due to tire pressure and more than likely driver as well. Those would be the top two impacts.

 

Oh, and at higher speeds, the tire pressure is a priority. Reminds me "again" to get it checked. I'm running snow tires that are now likely only set at 35 from the desired 39/36. I might even go to 40 for this winter. So if I'm back averaging 40 this winter, that would be nice. Last winter killed me, mostly very short trips, ice storm, idling, etc...

 

I totally agree with you that proper tire pressure is a must.

Thing is you state that some of your highest mpg trips have been cruising at 70-75 mph.

The point a lot of us are trying to make is that if you /anyone travelled at 60 mph as opposed to 75, you would do significantly better on the mpg side of things. I understand the need to get where you are going and choice is obviously yours on how you get to where your going. On that 80 mile commute one wonders how much time is saved going 75 instead of 60.... My guess is 10-15 mins or so. Leave 10 mins early and reap the benefits of better mpg and a more relaxed drive....

I think the math is something to the effect of 3 mins saved traveling 75 mph instead of 60 mph for every 15 mins travelled....

 

No question that a bit slower achieves better mileage. But unless conditions dictate otherwise, I'm simply not going to drive 60 mph on the interstate. And if my mileage is 15% lower by driving faster, trust me, the minutes saved are worth far more than the gasoline used. There is an alternate, parallel secondary road I could use, speed limit is 50 mph, and a bit slower through towns. It might add 20-30 minutes a day to my commute, but my mileage would be higher.

 

Urban driving fuel efficiency is affected by:

1) number of full and complete stops ( as number of stops increase overall fuel efficiency drops) - planning your driving route to minimize the number of complete stops needed is one of the easiest way to increase fuel efficiency without working too hard.
2) length of each trip (as trips increase over 30 minutes per trip the fuel efficiency increases) - doing several short trips in sequence so that each subsequent trip uses the residual thermal heat generated by the previous trip - improves fuel efficiency significantly in the winter time.
3) the top speed of a trip ( as speed increase over 35 mph/ fuel efficiency drops)
4) the driving temperature (as the driving temperature drops lower than 55 degrees fahrenheit the fuel efficiency drops) - grill blocking helps with thermal ice efficiency in the winter when driving at non highway speeds. In really cold regions, preheating the Prius coolant for about 30 minutes with a Toyota OE 400w Engine Block Heater before doing a cold start can improve fuel efficiency. The shorter the trips - the higher the cold start penalty is for driving at low temperature.
5) the more the hydraulic brakes or the regenerative brakes are used the lower the fuel efficiency tends to be. With respect to braking - anytime you have to brake at more than 15 mph - you are probably wasting energy/fuel. The reason cruise control (cc) doesn't always produce the best fuel efficiency is because the route is too hilly and the cc will use the regen brakes to slow down the Prius to the set speed when the Prius speed increases on the downhill. However, the electric conversion from regen braking is lossy at best 50% efficiency ... cc is only energy efficient when the road is flat.
6) the higher tire pressure equates to less tire rolling resistance which increases a car's fuel efficiency.
7) if a Prius must stay powered on while stuck in a traffic jam for longer than 12 minutes in below 50 F degree weather - fuel efficiency will drop. Traffic jams during the summer have less impact on fuel efficiency. Planning your route to avoide traffic jams helps improve fuel efficiency.
8) The Prius gets better fuel efficiency if the Prius accelerations timed when the Prius is moving downhill. The Prius benefits significantly from gravity assisted acceleration/ slingshot accelerations because its high curb weight.
9) use 100% gas for the most power and best mpg --- avoid ethanol if you can
10) if you want to learn how to hypermile a Prius - nothing beats a ScangaugeII - while the ScangaugeII is not the most hi tech device - it is the best documented and accessible tool for those trying to learn how to hypermiling outside a class room environment.

For some perspective on achievable fuel efficiency on the super highway: when I drove in the rain and wind going at an average of 75 mph on the OH turnpike in the cold - my 2010 Prius 3 getting about 44 mpg with E10 gasoline (with the tire pressure set at 40 psi front 38 psi rear).

My overall MPG performance is unusually high because I am a hypermiler. My mileage goes up in the summer and down in the winter no matter how hard I try to hypermile. - long highway trips usually lower my fuel efficiency. My complete mileage log for my 2010 Prius 3 for over 55,000 miles is available for review at cleanmpg.com under Hyper Drive 1 and at fuelly.com under HyperDrive One. My 2010 Prius MPG seasonally adjusted performance represents its upper limit of fuel efficiency performance when not enhanced with a plug in battery or EBH. I am persistently in to top 5 percent of all drivers wrt MPG - Your mileage may vary...



hope this helps
Walter

 

Thank you for posting this, Walter. As a soon to be 2015 Prius v (lowercase v for the Prius v) owner, this is exactly what I needed to know to achieve the best fuel economy possible.

 

Great info Walter, thanks for posting.

I didn't realize that the cc used regen to slow down to maintain speed on down hills (makes perfect sense though now that I think about it). I just always noticed that with cc on and while traveling down a hill my instant mpg and the graph usually shows 99 or close to it, guess I always just though that the car went into a type of automatic glide?

I never really noticed the regen bar moving up with cc on and going downhill but then again my commute does not have much elevation change at all, I can see how cc could be counter productive in the mountains or real hilly areas though.


And on another note, I just recorded my worst tank thus far. Granted it has been bitter cold most everyday these last 2 weeks. 37.025 mpg calculated is all I could muster, 40.3 mpg indicated (8% variance, how weird) 362 miles travelled, Pitiful considering I have been using cc at 55 every commute except for yesterday where I was running late and drove a lot faster than normal.

Now I own a persona, not a v, and my commute is only 18 miles each way, if it were longer I'd prob do better. I posted above to show that, even if you do most things right (I drive slow, use cc, psi set to 44/42, use the heater set to no more than 67-69 and on auto, try to p&g if I remember...) the extreme cold weather really takes it's toll on mpg unfortunatley.

So I can easily see how mid to low 30's for mpg are possible In a bigger an heavier v during this extreme cold weather going 20 mph faster than I do on average on the highway, tires not pumped up, heater set to 74 as op stated, not using p&g, etc.

Once it warms up I'm sure everyone's mpg will increase...

Come to think of it, I need to install the grill block pipe insulator things I bought a couple weeks ago and forgot about....might help so I hear..