proposal for mandatory/copy & paste fuel economy questionnaire

How about a real question !!!!!!!

Having a new 2010 III when I took delivery last week, on the fuel that was in the car......I averaged 54 MPG on the dash......after filling the tank & resetting the trip meter.......I'm trying to get it to 46 MPG......not easy to get this.

Question is why the large difference...the temperature outside has not changed that much.....driving habits are the same

any ideas ????????

 

The MID is about 7% optimistic. I had that kind of variation over my August tanks. Usually the 1st tank is low as it may not be full. EVERYTHING affects fuel economy. One tank isn't enough data. It'll take 3 or 4 to see a trend. Inflating the tires & blocking the grill will help but the biggest improvement comes when the nut behind the wheel is adjusted.

 

winter fuel? that might account for a few mpg's

 

Call the dealer and ask what brand of gas they use. Buy the brand for two tanks and try again.

Bob Wilson

 

I hope this is the right place to post this!

- Have you read This Thead Yet?
Yes

- What fuel economy are you getting and how are you determining fuel economy? (trip computer or manual calculations)
Everyday it goes down .5-.8 MPG. It was at 37.4 on Friday and it's down to 33.1MPG currently

- What fuel economy are you expecting and why?
33.1, I'm guessing because work is just outside of town and it's about a 3 mile roundtrip. It starts up cold and never gets the chance to warm up, however I'm not going to drive it for 15 minutes before just so the numbers appear better.

- What are the approximate outside air temps?
10-20F

- How long are your trips?
Like I said, maybe 3 miles. If I run errands, anywhere from 5-8 miles

- 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?
Currently its 100% city. I averaged 33-38 MPH unless there's a stop light.

- What region/state are you in? (if you haven't set your location in your profile)
Tiffin, OH
- What's the terrain like of your drives? (e.g. flat, gentle hills, steep hills, etc.)
Mostly flat, two slight curves where it slows down to 25 MPH and maybe a tiny dip down inbetween the curves.
- Is your oil overfilled? (i.e. above the full mark on the dipstick)
I don't know. I will check it out, however its 12 degrees here and freezing lol
How old is your 12v battery? What is the voltage reading of your 12v battery after sitting over night? (Method Here)
I have no clue, I picked this car up at the dealer on Thursday. 99k miles, would anything be changed? I will tell the dealer to fax me over the carfax they have on file.
Have you had your alignment checked? Any pulling or abnormal tire wear?
I personally have not. The tires I have suck, Riken Raptors. They are terrible in snow, the dealer said 75% life left on them.
- 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).
Riken Raptor.. not sure the model and size. How can I find this out?
- What are your tire pressures?
Unknown, going to a gas station to fill them up. I'm guessing they are low since the cold here is pretty frigid at times.
- 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.)
2003 Toyota Matrix XR 4WD 1.8 4CL. I think maybe 20-24 MPG in city?
- How are you trying to drive (e.g. trying to stay in electric only?) and how hard are you braking?
My driving habits still remain and I'm trying to break them. I brake pretty hard still and I do my best to stay in electric. I tried the P&G but I don't think I have all of the info I need.
- Are you "warming up" the ICE (internal combustion engine) by letting it idle after powering on?
yes. I wait to the light on the car says ready.
- Are you driving using D or B mode?
D mode.
- HVAC settings? Are you using the heater, AC, auto mode, etc.? If using auto, what temp is it set to?
I have defrost on because its too cold not to. I turned off AC mode thinking it would help, does it?
- 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?
nothing to my knowledge, I may just need a tire pressure increase and to block the grill. I was hoping for over 40MPG in the winter. I would be content with that.

Thanks for helping me out everyone.

 

I agree with your assessment, check tire pressure and increase to 40 psi or so and block the grill. Check the grill blocking threads for the model of Prius you have, with the Gen3 we usually block the bottom, and if I remember correctly we block the top part with the Gen2. (It would be helpful if you included the year of your Prius.) There are a lot of grill blocking threads, here is one: http://priuschat.com/forums/gen-iii...62556-2010-prius-grill-blocking-strategy.html

Short trips and cold weather are a problem with any car including this one. A block heater would help. Having the defroster on shouldn't matter if it is below 25 or 30 degrees F, at warmer temperatures the AC runs with the front defroster but not when it is so cold.

I think you might be able to increase your mileage a little but don't expect to much with all the short trips until spring.

 

I suggest using one of the two Trip meters to display daily MPG. Reset it in the morning and watch the patterns. This will provide an immediate indication about what is happening, and more consistent feedback to help you improve. A tank or lifetime MPG display changes too slowly and inconsistently for daily feedback, so leave that on the other trip meter.

And under your conditions, the daily numbers will be low enough to really cringe.

This short a commute will produce terrible MPG in the best weather ...

.. and horrible numbers in this weather.

Because of warmup requirements, all internal combustion engine cars will produce rotten MPG over this distance. Prius is merely not as bad as the others. For this distance, the best efficiency comes from an electric car, plugin-in hybrid, bicycle, or walking shoes.

Dealer and CarFax will know nothing about the 12V battery, which is a regular maintenance item that doesn't rise to the attention of resellers.

Do check. Many drivers don't, so your car could easily have arrived with random or low pressures.

Until you are more familiar with the car, don't try to stay in electric, let the car make that choice. All energy comes from gas, and laundering it through the battery is less efficient except in special circumstances. You will become familiar with those with experience.

'Ready' does not mean warm. But if your windows are clear, don't wait for the engine to warm.

With your short commute one way, that will be very challenging even in the best weather.

40 MPG for 1.5 miles requires 0.0375 gallon. On a recent icy morning (25F), my ScanGauge displayed 0.04 gallons burned by the time I scrapped the ice of the windows, and the engine temperature was up to only 125 degrees, still well below full operating temperature. At the time it reached the bottom on the hill, two miles away and 400 feet down, it had burned 0.06 gallon, and wasn't fully warm. Your level drive will probably take a bit more fuel.

The day before with similar ice, my four cylinder Subaru burned 0.06 gallon while clearing the windows, but had burned 0.17 gallon by the bottom of the hill. But by continuing to burn fuel while coasting downhill, it did reach full temperature.

 

Mostly I have outer temperature more than 35 C. And in 4 months of the year the temperature goes upto 45 c.

 

Question: Toyota dealership service manager in Valencia, CA advised me that 2008 Gen II Prius gas engine would "NOT" start immediately if "Climate" settings included: Temp set at other than "Cold" and A/C off and Auto off. I tried set all three to the positions he suggested. The gas engine did not come on until 20 mph the first time with all 3 settings. However since then, gas engine comes on at 15 mph or as soon as I start up. Why the intermittant gas engine operation?

 

Thanks for the forum direction regarding the 2008 Prius Gen II ICE starting question. Mike

 

[FONT=&quot]

- What fuel economy are you getting and how are you determining fuel economy? (trip computer or manual calculations) [/FONT]
-
- [FONT=&quot]I am getting roughly 40MPG according to the trip computer.[/FONT][FONT=&quot]

- What fuel economy are you expecting and why?[/FONT]
- [FONT=&quot]I am expecting roughly 53MPG as claimed by Toyota.

- What are the approximate outside air temps?
60F
- How long are your trips?
5-10 miles[/FONT]
- [FONT=&quot]
How old is your 12v battery? What is the voltage reading of your 12v battery after sitting over night?[/FONT]
- [FONT=&quot]My car is brand new[/FONT][FONT=&quot]

Have you had your alignment checked? Any pulling or abnormal tire wear?
I assume the dealer should have done this.[/FONT]
- [FONT=&quot]
- 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?
[/FONT]I do 95% city driving, 5% highway.
[FONT=&quot]
- What's the terrain like of your drives? (e.g. flat, gentle hills, steep hills, etc.)
Mostly flat, with some small hills[/FONT]
[FONT=&quot]
- What are your tire pressures?
Don’t know[/FONT]
[FONT=&quot]
- Is your oil overfilled? (i.e. above the full mark on the dipstick)
Don’t know[/FONT]
[FONT=&quot]
- 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.)
2004 Honda Accord base model with base engine. EPA rating is 21 in city. I actually got 15 MPG.[/FONT]
[FONT=&quot]
- What region/state are you in? (if you haven't set your location)
MA
- How are you trying to drive (e.g. trying to stay in electric only?) and how hard are you braking?
I try to drive as conservatively as possible. I try not to brake too hard.
- What modes are you using, if any? "normal", EV, power, eco?
Eco mode.[/FONT]
[FONT=&quot]
- Are you "warming up" the ICE (internal combustion engine) by letting it idle after powering on?
No[/FONT]
[FONT=&quot]
- Are you driving using D or B mode?
D[/FONT]
[FONT=&quot]
- HVAC settings? Are you using the heater, AC, auto mode, etc.? If using auto, what temp is it set to?
I am not using anything.[/FONT]
[FONT=&quot]
- 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).
Yes[/FONT]
[FONT=&quot]
- 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?[/FONT]
I am not reporting a mileage drop.

 

Re: RFC: proposal for mandatory/copy & paste fuel economy questionnaire

- What region/state are you in? (if not already set by the user)
Arizona
- What fuel economy are you getting and how are you determining fuel economy? (trip computer or manual calculations)
Manual calculations average 5 tanks 44.5 mpg
- What fuel economy are you expecting and why? I was expecting a little under sticker 47-49mpg. Maybe a better term would be hoping.
A little change in driving habits should achieve that.
- Make, model, year, engine and transmission of previous car? (e.g. 08 Honda Civic Si 2.0L 4 cylinder, manual transmission) What was its EPA rating and what did you get on the same trips/commute? (EPA ratings can be found at www.fueleconomy.gov.)
Last car - 2011 Prius II
- What are your tire pressures? 35/33 as of just recent.
- What are the approximate outside air temps? Currently (May) 100-105 high...77-84 low
- How long are your trips? Work 16 miles one way, everything else within that range except for a friend's that is 25 miles one way.
- 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? I do about 80-90% highway driving. Average speed 70-75.
- What's the terrain like of your drives? (e.g. flat, gentle hills, steep hills, etc.) gentle inclines up and down on freeways.
- How are you trying to drive (e.g. trying to stay in electric only?) and how hard are you braking? Before I drove pretty aggressive and didn't care of MPG, this tank I'm on now I'm trying to brake gradual, with increase speed/gas on downward slopes on highways and gradual/let off the gas when approaching upward slopes.
- What modes are you using, if any? "normal", EV, power, eco? Power 100% of the time.
- Are you "warming up" the ICE (internal combustion engine) by letting it idle after powering on? I drive immediately after turning power on.
- Are you driving using D or B mode? D
- Is your oil overfilled? (i.e. above the full mark on the dipstick) Not sure, haven't checked.
- HVAC settings? Are you using the heater, AC, auto mode, etc.? If using auto, what temp is it set to? AC all the time even in the early morning. On 75 reg mode.
- 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). Yes
- 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?

 

NMW1982
I answered you over in this thread
http://priuschat.com/forums/prius-c-fuel-economy/109256-low-mpgs-new-prius-c.html#post1558325

 

@ kalome re your 2012 Prius Liftback III:

Pretty much standard stuff:

(1) Slowing down will increase mpg (staying in the right lane of course). Not saying you can or want to go this slow, but I drive from my home in CT to Boston often and usually manage around 70-72mpg actual from here to there at around 50mph. Of course this is a longer trip and you won't reach that average when you are warming it up from cold and going just 15 miles, but it gives you an idea of what is available. I had to use cruise control to slow myself down - not the most efficient way to get mpg but with it on I could keep my right foot OFF the gas pedal. Takes a while to get used to going slower.

(2) Reducing AC use as much as you can. I try to manage with the AC set about 2 degrees F under the outside temp and that doesn't impact the mpg too badly. It also helps to park the car in the shade if you can, and/or use a front window screen, so on the way home you are using as little AC as possible to cool the car down.

(3) Bumping tire pressure up to the sidewall rating, which is 44PSI on my OEM's. If your car came with 17" rims that might cost a bit of mpg.

hope this helps. Good luck!!

 

Insight Owner - Thanks for the response.

1.) 50mph - That is way too slow for most of my commutes which is on the freeway where posted speed limit is 65mph. Also driving this slow would not be worth it since I do not like driving that way and it would take me at least a few minutes longer getting from point A-B then driving 75mph.

2.) I live in Arizona where it is extremely hot from May to September with our lows as high as 95-100 & 110-118 high in End of June/July/Aug. Right now we have been hitting the 80s for the low and 100-105 for the high.
AC is a must on all trips. I haven't been using Auto & Max, I use it as low setting as tolerable using manual fan/AC. If it is above a hundred and the car is sitting in the heat while I am at a store I will max out the fan with AC until it cools down enough to lower the setting.

I always park in the shade..home & work. The only time I do not is when it is not available, like going to the store.
I do own and use a front sunscreen.

3.) I have 15's. I did notice before that the max is 44 psi but I was afraid of the tire wear and inflated them per Toyota Prius Manual for 15 inch tires @ 35/33.

 

Just so you understand that speed is one of the major determinants of mpg: alas, there's no angel dust you can get that will increase your mpg at higher speeds! As someone here said, that's why the laws of physics are "laws" and not "suggestions". Aero drag increases as the square of the speed.
I felt much the same way as you do until I tried slowing down and discovered that I was far less stressed and didn't lose as much time as I expected. PSL's around here are 65mph and I've been driving 50mph since 2007, no problems.
It's a tradeoff that you'll have to accept: if you go for the mph, don't expect the mpg.

Yeah, I'm quite familiar with AZ, having driven through it many times in cars without AC. Worst experiences in the SW?: (1) driving through the Mojave Desert one afternoon, stopping for gas, and discovering that the temp was 120F - knew it was hot, but thought it was "only" around 105; (2) driving through Vegas at midnight on my way back from CO and Zion Nat'l Park. Temp was 103F at midnight, and the metal accelerator pedal was blistering the sole of my foot through my sandals. How did we survive?

Anyhow, you're clearly trying to minimize AC use.

Experience has been that tire wear is actually less and more even at higher pressures. Seems surprising, probably has to do with the stiffness of the treads of modern steel belted radials. Old bias ply tires didn't work that way. I don't worry about going to the sidewall rating. There's less flex at higher pressures, so the tires heat up less as you drive. Underinflated is very dangerous because increased flex puts a lot more heat into the rubber.