Something wrong with my Prius II - It takes more gas than it advertised.

[hschen]

Hello,

My wife took the delivery of our Prius II (in Winter Gray) in Phoenix last week and drove it to Irvine the next day. I instructed her to drive carefully - not to exceed 75 miles per hour and don't brake hard and coasting a lot. On her trip to Irvine, Prius returned only 47.8 mpg (displayed). I drove Prius the last 2 days and tried very hard to get high mpg by driving according to the ECO display and instant MFG display. In mostly all city driving, I never saw average mpg better than 50 yet !! No matter how slow and smooth I did (cars behind me were passing me and gave me the look), I don't see 51 mpg as advertised, not to mention 60-70 as some of you claimed you achieved. I only got about 46 mpg in mixed city driving in 2 days.
This morning coming to work, in the 36 miles of freeway driving on I-405, the average mpg rised to 48.8 mpg. I still don't see the ave 50 combined mpg. I suspect something not right with my Prius. A bit out of tolerance engine which may still within the manufacturing spec could consume more fuel than normal. I am really wondering how you guys/girls achieved the high 50 mpg. I saw a few even claimed high 60's. How could that possible? Crawling speed all the time?
How many of you out there are in the same boat as I am - suspecting our Prius is one of these under performing product from Toyota?

[qbee42]

Give it (and yourself) some time. The car will break in, and your driving techniques will improve.

Tom

[Zythryn]

Is it a Prius gen 2 or 3? You mention a Prius II, not sure if that is the generation or the package.
For a Gen 2 you are right at the stated mpg of 46.
Forgive me, I am not sure how far it is from Phoenix to Irvine, but many people see better efficiency once the car is 'broken in'.
Anything over 60mph and the air resistance will start cutting into your efficiency. The EPA tests which generate the 51mpg are, I believe, tested at 55mph for freeway.
Speed under 50-60mph isn't much of a factor, how you drive is more of a factor. However, it sounds like you are driving just fine. You may just see the efficiency improve as the car gets broken in.
Oh, that and check the air pressure in your tires, if the pressure is low, that can hurt your mileage as well.
Being stuck in an area where the typical speed on the freeways is 70-80mph there isn't much you can do, but you should do well on city streets.

[a64pilot]

Not knocking you, but it seems that most of these "I'm not getting good mileage" threads generally up with us finding that the owner can't accelerate slow, it's not polite or safe and "I'm only doing 80 on the freeway" how slow do you want me to go?
I get around the lower 60's, but haven't been on the freeway, never exceed the speed limit, use the economy mode, almost never go into the power portion of the HSI, and glide whenever possible. I try to look at least a half mile ahead of me and if traffic necessitates and or to hit a light right, I will start coasting quite a ways away. Brakes are the enemy, momentum is your friend.
My one concession is that I will set the A/C to 72. I know the energy is coming from the gas tank, but I won't to be comfortable.
Leave a little early. set back, slow down and enjoy the ride. Take the scenic route, you will be surprised how little time you saved by hurrying and how much more relaxing and calmer you will be when you get there.

[hschen]

Thank you, Zythryn.
I have a Prius Gen III Model II.
It's about 350 miles from Phoenix to Irvine.
Prius supposes to return better mpg in city than on freeway according to the advertised numbers - 51 city and 48 freeway. I just don't see that, yet, maybe, and hopefully ... and I am frastrated in not getting high mpg as I tried so hard so far.

Originally Posted by Zythryn

Is it a Prius gen 2 or 3? You mention a Prius II, not sure if that is the generation or the package.
For a Gen 2 you are right at the stated mpg of 46.
Forgive me, I am not sure how far it is from Phoenix to Irvine, but many people see better efficiency once the car is 'broken in'.
Anything over 60mph and the air resistance will start cutting into your efficiency. The EPA tests which generate the 51mpg are, I believe, tested at 55mph for freeway.
Speed under 50-60mph isn't much of a factor, how you drive is more of a factor. However, it sounds like you are driving just fine. You may just see the efficiency improve as the car gets broken in.
Oh, that and check the air pressure in your tires, if the pressure is low, that can hurt your mileage as well.
Being stuck in an area where the typical speed on the freeways is 70-80mph there isn't much you can do, but you should do well on city streets.

[ksstathead]

Are your tires at or near max sidewall?

Are you accelerating too slowly and/or failing to properly execute glides?

If you always accelerate like granny (no offense grannies), then try faster (normal) acceleration, coupled with gliding (see pulse & glide).

Does the car pull left or right? Some report needing alignment (free) after the ride on the boat.

[hschen]

Thx, ksstathead.

My tires are new and at full pressure, I am sure.
I have been accelerating like granpa (too slow by any standard) in trying to stay in ECO mode. Too slow will decrease mpg? Then, someone please teach me how to drive for best mpg.

Originally Posted by ksstathead

Are your tires at or near max sidewall?

Are you accelerating too slowly and/or failing to properly execute glides?

If you always accelerate like granny (no offense grannies), then try faster (normal) acceleration, coupled with gliding (see pulse & glide).

Does the car pull left or right? Some report needing alignment (free) after the ride on the boat.

[efusco]

Please read:
New owner? Want MPG help? Read this first.

[wfolta]

Originally Posted by hschen

Thx, ksstathead.

My tires are new and at full pressure, I am sure.
I have been accelerating like granpa (too slow by any standard) in trying to stay in ECO mode. Too slow will decrease mpg? Then, someone please teach me how to drive for best mpg.

Welcome!

First, the EPA mileage is an estimate. As the saying goes, "Your mileage may vary". There's no way a single number is going to summarize how a car will perform across an entire continent, and across a variety of weather from sub-zero temps and snow, to 3-digit highs, or torrential rains, not to mention varying geography and traffic patterns. You aren't guaranteed to get a certain mileage, the EPA is a guide that allows you to compare cars.

That said, I believe it's fairly straightforward to get 50 MPG overall. And with the usual increase of mileage as the car breaks in over the first 1,000-2,000 miles, you'll easily hit 51 MPG, based on your initial numbers.

Second, I might recommend my article, which you might find useful.

(In answer to your question, yes, super-slow acceleration will hurt mileage. So will heavy -- as in you set it to 70 and it's 95 out -- air conditioning use, just as with any car.)

[hschen]

Thanks a lot, wfolta. I read your post.

Yes, AC should be a factor as SoCal was hot in the past weekend. I will try to drive more normally now and not glue to the ECO display all the time which is a danergous behavior on the road. If mpg don't improve after 1000 miles or so, I shall bring it back to my dealership for an analysis.

Originally Posted by wfolta

Welcome!

First, the EPA mileage is an estimate. As the saying goes, "Your mileage may vary". There's no way a single number is going to summarize how a car will perform across an entire continent, and across a variety of weather from sub-zero temps and snow, to 3-digit highs, or torrential rains, not to mention varying geography and traffic patterns. You aren't guaranteed to get a certain mileage, the EPA is a guide that allows you to compare cars.

That said, I believe it's fairly straightforward to get 50 MPG overall. And with the usual increase of mileage as the car breaks in over the first 1,000-2,000 miles, you'll easily hit 51 MPG, based on your initial numbers.

Second, I might recommend my article, which you might find useful.

(In answer to your question, yes, super-slow acceleration will hurt mileage. So will heavy -- as in you set it to 70 and it's 95 out -- air conditioning use, just as with any car.)