Is the computed MPG real?

[jamesaspinwall]

Hi,

Just got my Prius yesterday and drove it to work today. My commute is 21 miles long with half of it rolling hills and turns. I reset the MPG before I started my driving and when I arrived the computer shows 52.3 MPG. Is this realistic, or is it computer wishful thinking(computing)?
If I got this kind of milage I would be in hybrid nirvana I can't wait until driving up to the gas station to validate the computer :-(

[chuck kershner]

<div class='quotetop'>QUOTE(jaspinwall @ Apr 9 2007, 03:46 PM) [snapback]420349[/snapback]</div>

Hi,

Just got my Prius yesterday and drove it to work today. My commute is 21 miles long with half of it rolling hills and turns. I reset the MPG before I started my driving and when I arrived the computer shows 52.3 MPG. Is this realistic, or is it computer wishful thinking(computing)?
If I got this kind of milage I would be in hybrid nirvana I can't wait until driving up to the gas station to validate the computer :-(
[/b]

Must be nice. I've had my 06 Prius since mid-September 2006 and the best I've gotten was 49 mpg during the first 600 miles. Since then, nothing better than 39. Filled up 4/9/07 and mpg read 42 during the first mile and then dropped to 21. However, only have driven 6 miles on this tank so far. Perhaps a 30 mile round-trip on Wednesday will get it back into the 30s. But from the posts on this site, off-the-scale mileage seems to be the rule rather than the exception, so I may have the only Prius that gets 30-40 mpg consistently. Life's too short to obsess over mpg.

[jkash]

<div class='quotetop'>QUOTE(jaspinwall @ Apr 9 2007, 12:46 PM) [snapback]420349[/snapback]</div>

Hi,

Just got my Prius yesterday and drove it to work today. My commute is 21 miles long with half of it rolling hills and turns. I reset the MPG before I started my driving and when I arrived the computer shows 52.3 MPG. Is this realistic, or is it computer wishful thinking(computing)?
If I got this kind of milage I would be in hybrid nirvana I can't wait until driving up to the gas station to validate the computer :-(
[/b]

After 35,000 miles and three years, my calculated MPG is little over one MPG less than what the computer says. Others here on PriusChat have similar results.

[adam1991]

so I may have the only Prius that gets 30-40 mpg consistently.[/b]

no, that's where mine is hanging out, too.

That would be fine. Toyota has given us a car that drives just like we expect, only it's getting 1.5x to 2x the gas mileage while we drive it like that. Can't really argue with that.

[jamesaspinwall]

I just want to point out that my driving is about 30 to 45 MPG, with few stops and it seems that my driving is efficient. While my wife gets 24 MPG in the Camry, I get about 29 MPG in the same car. I am very light footed, on the gas and the break.
After begging for two years, finally my wife let me buy my toy. What a difference from my 15MPG SUV! Needless to say, I love my Prius :-)
Cheers.

[daveleeprius]

Mine started out at 42mpg when we bought it with 28 miles on the clock, and now it reads 43.1mpg. It doesn't fluctuate at all, it stays consistant. Never been below 42, never been above 43.1 and we've around 3500 miles now.

Dave

[jamesaspinwall]

I meant to say 30 to 45 MPH.

[qbee42]

<div class='quotetop'>QUOTE(jaspinwall @ Apr 9 2007, 04:46 PM) [snapback]420349[/snapback]</div>

Hi,

Just got my Prius yesterday and drove it to work today. My commute is 21 miles long with half of it rolling hills and turns. I reset the MPG before I started my driving and when I arrived the computer shows 52.3 MPG. Is this realistic, or is it computer wishful thinking(computing)?
If I got this kind of milage I would be in hybrid nirvana I can't wait until driving up to the gas station to validate the computer :-(
[/b]

It's real, within a very small margin for error. Nice, huh.

Tom

[Bill Merchant]

The computed MPG is based on a sum of the pulses from the wheels with each rotation, for distance, divided by the time the injectors are open, for fuel volume. Standard tires are 855 revolutions per mile. These are both fairly tiny increments and the computed fuel efficiency is fairly accurate.

Tracking your fuel efficiency by taking miles driven (to the nearest tenth, or 528 feet) and dividing by gallons (to the thousandth, or 0.128 ounce) is complcated by the variability of the volume of the gasoline bladder and the fact that gasoline volume is not standardized for temperature or energy content. Over time, maybe a year, the computer MPG and hand-computed MPG will converge. Don't get upset if your hand-calculations are way off from the computer. It's still better fuel economy than you'll get in almost any other vehicle.

[JimN]

<div class='quotetop'>QUOTE(jaspinwall @ Apr 9 2007, 03:46 PM) [snapback]420349[/snapback]</div>

Hi,

Just got my Prius yesterday and drove it to work today. My commute is 21 miles long with half of it rolling hills and turns. I reset the MPG before I started my driving and when I arrived the computer shows 52.3 MPG. Is this realistic, or is it computer wishful thinking(computing)?
If I got this kind of milage I would be in hybrid nirvana I can't wait until driving up to the gas station to validate the computer :-(
[/b]

I find the MFD to be a bit optimistic compared to my calculations but a reasonably good estimate. Start shopping for gas a 2 pips, really consider buying gas at 1 pip. BUY GAS WHEN THE PIP FLASHES!

Bottom line--enjoy the car. Don't get hyper about the mpg. BTW, did you inflate the tires to 42/40?