Break-in period mileage - normal?

<div class='quotetop'>QUOTE(YvesKlein @ Sep 2 2006, 05:38 PM) [snapback]313184[/snapback]</div>

I just hit 5,000 miles and changed the oil. My mileage for the last 2,000 miles is consistnetly between 50 and 50.5 MPG. I drive 120 miles round trip, to and from work, 80% highway, 20% local with speed varying between 0-40 and up to 80 on the Long Island Expressway.
I did increase the tire air pressure, front 40, back 38, and drive conservatively when off the highways.

 

Hi YvesKlein!

I, too, am a new Priuse owner...got my car 7/18/06...I have the worst kind of driving conditons..lots of short daily trips up and down loads of hills...my first tank was 30 mpg.

I have to say, though, that I do see the effects on my mileage when I apply the suggestions I gained here....

I bunch my errands, so that the ICE warms up and stays that way.

I upped my tire pressure to 40/38..could go higher still.

I am finding the best way to drive my local area...since I NEVER drive on the parkway...ever....

Second tank was 41-42 mpg...and now, on my third tank, I am around 42 mpg.

I find that if I don't struggle to get into Pulse & Glide, since many of my streets the speed limit drops below 30 mph, the car works with me...or it seems that way....

So...on several stretches where there are some easy inclines and some declines, I find that the car goes into all-electric mode (all yellow arrows) as I drive these stretches...and then, it even goes into "glide" (no arrows) in the 20+ mph range, although the range for glide is usually 30-40 mph...

State of Charge (SOC) is a factor (AC, weather, also)....so I don't worry about these stretches of all electric, since somewhere along the way I have some long downhill coasts that regenerate the battery...

So...enjoy the car! Read a lot here...there is much to learn from others' experiences.

I happen to love the fun of trying to up my mpg....but, bottom line,

safe driving....

enjoy the car....

Welcome to Prius from another Newbie!

terri

 

Yves,

Welcome to the chat! I was really laughing at first when I read your post thinking you were goading us "REALLY ASTONISHINGLY LOW FUEL EFFICIENCY". I just assumed that you had probably read Efusco's article and a few threads and knew that there are folks happy to do 40's. Then I felt bad because you might not know this.

Any who, let's use Efusco as an example at 90F (that's kind of LA right?) he puts in about 9 gallons (you can click on his spreadsheet):
175 miles @ 4.5 gallons = 39 MPG ... Not too bad!

The guage isn't very accurate, however, so maybe 5 gallons have been consumed, eh? 35 MPG for a 90F fill up.

Now let's just say when the tank was filled it was 57F like my temperature, then you would only put in about 6-7 gallons:
175 miles @ 3.5 gallons = 50 MPG! Good Golly Miss Molly!

OK, OK, ... Adjusting for the guage 43.8 MPG
Hey I'll trade you any day! Enjoy the joy of your first tank, blessings!

 

noticed improvements at 5000 and 8000 miles to keep the faith!

 

I'm surprised no one mentioned it but "miles per tank full" is really not a very good way to measure mileage. Due to the bladder the old way of computing mileage, miles driven divided by gallons to fill the tank, doesn't work very well either unless you compute it over quite a few tanks. Best to use the MFD mileage.

Then what you should get depends on where and how you drive, the temperature, etc. If you post that kind of information we might be able to tell you if you have a problem with your car, your driving, etc.

Quite a few people who are apparently objective observers have posted here that their mileage improved as they put more miles on the car. I believe them but in my case I noticed absolutely no improvement due to "break in". It took me 2 or 3 tanks to learn how to drive the car efficiently, after that mileage seems to depend on where I drive, winter or summer gas, and things of that nature. No big jumps in mileage.

 

When I traded in my 04 for an 05 I was surprised to see no difference in mpg's. I got 48-50 with the 04 and from day one got 48-50 with the 05

 

[attachmentid=4818]<div class='quotetop'>QUOTE(paprius4030 @ Sep 3 2006, 04:45 PM) [snapback]313574[/snapback]</div>

 

<div class='quotetop'>QUOTE(YvesKlein @ Sep 3 2006, 12:18 AM) [snapback]313382[/snapback]</div>

I made two assumptions:
1. that when the dealer was warning you it was because when the weather was warmer, afternoon, he'd been getting in 11.9 gallons, thereabouts, so I was guessing that you must be hitting 100 in the afternoon and at or below 90 in the morning. Which is pretty hot from my days in Pasadena.
2. Efusco's spreadsheet was handy and pretty much showed 90 9 gallon fillup so it was simply convenient.

You'll have to run your own numbers of course but to answer the question is your MPG reasonable, this guessimate is pretty prudent, eh?
<div class='quotetop'>QUOTE(tumbleweed @ Sep 3 2006, 02:47 PM) [snapback]313559[/snapback]</div>

Of course, you're right, but he gave enough information to presume he's in the ballpark yes? Here's a question for you tumbleweed. Several posts I've read of folks who just cancel their current MPG with the reset, admittedly some do this to "feel better". Just this year I've started writing down the MFD MPG as well.

For these 'resetters' just how accurate is the reset MFD MPG on the same tank?

Hey Aviator, what happened to your post? Welcome to the boards

 

[attachmentid=4819]<div class='quotetop'>QUOTE(aviator @ Sep 3 2006, 05:55 PM) [snapback]313613[/snapback]</div>

Well, I guess y'all can tell I'm a rookie with the posting of a blank message! I have been lurking for several weeks and I have learned much from many contributors. I believe many of the things I've learned have had considerable positive impact and I want to say thank you!

My fuel economy experience has been very satisfactory from the day I picked up my Prius. As will many of you, my first "Dealer Filled Tank" did not deliver stellar MPG. However, my 2nd tank had racked up 611 miles before I refilled (with a "flashing pip"). My 3rd tank surpassed that with 651 miles! I am averaging just over 51 MPG including the "Dealer Fill-up" which left much to be desired. I drive with the A/C set on recirculate and 78 degrees temperature. I commute 25 miles round trip on a gently rolling 2 lane highway with a 55 MPH limit. I have attempted to attach my Excel spread sheet (thanks to another poster for the setup) so that you can see my experience to date.

 

great spreadsheet!

 

The biggest effect on gas mileage for me was "driver break-in". Once I became one with my car, my gas mileage was where it was supposed to be. Until then, it kind of crept up as we were getting acquainted.

There was also a minor effect from inflating the tires to 42/40, and from break-in. But the biggest moves up in gas mileage were from understanding how the car wants to be driven.

At least for me.

-Roger

 

<div class='quotetop'>QUOTE(FieroGT @ Sep 2 2006, 02:53 PM) [snapback]313194[/snapback]</div>

Wow FieroGT! I thought my 100 mile round trip commute to work was bad! I drive pretty much the way you do. I have just over 2500 miles on now and am seeing my averages up in the 49-51 mpg range.

 

well one thing you'll learn is not to base any judgements on the miles per tank. you never really know how much gas is actually in the tank, so focus more on the mpg. and if you calculate your mpg by using gallons filled and miles driven... you're going to see some real variation tank to tank, which will even out to a 1-2% difference over mfd values over time.

so just relax, keep an eye on the mpg readings that you're seeing on the screen, fill er up every now and again, and don't worry about the rest.

congrats on the new car

 

<div class='quotetop'>QUOTE(berylrb @ Sep 3 2006, 03:01 PM) [snapback]313616[/snapback]</div>

Good question, I don't have an answer, I've never tried to check that. I hope it's accurate and I suspect it is, I can't think of any reason the accuracy would change. I think the requirement would be to check it long enough to allow the computer to get some reasonable data. I have tried a couple of times to check the accuracy of the MFD mileage by going for several tanks and then trying to refill it to the same level, i.e. clear up to the top. I suspect all I did was compare the accuracy of the flow meter in the car with the ones in the gas pumps, but my tests did indicate the MFD was about .5 or .6 MPG better than what the gas pumps showed. Pretty close, and I wouldn't want to say which was off.

I haven't kept a record of every tank full but I did keep the first few and I still keep records of mileage when I make a change such as new tires or when the weather changes significantly. For those purposes I always check it over a tank full, usually 400 miles or more, and I try to start and stop the mileage test at the same location to cancel out altitude differences.

 

<div class='quotetop'>QUOTE(tumbleweed @ Sep 4 2006, 09:27 AM) [snapback]313952[/snapback]</div>

Thanks Tumbleweed! I have a hunch that it is accurate regardless of when the reset is hit. My thought is that since the MFD MPG is based upon internal injection system computations, that if one's tank or lifetime MPG is based upon it, then it really doesn't matter when one refills the tank, as long as enough gas is put in to reset, or do a manual reset.

So if one is "psychologically hindered" by a low MPG, just fill up and start over. Of course this does screw up one's chances for a miles/tank record.

 

<div class='quotetop'>QUOTE(aviator @ Sep 3 2006, 03:10 PM) [snapback]313623[/snapback]</div>

for the spreadsheet, if youre not too concerned about calculating price of gas, or daily figures, there's a website that does it for you.

Http://www.greenhybrid.com

go to compare database, and then create your login/car, and input your gallons that you fill up per instance and also milage travel. Voila. Nice and easy