March 2007 Averages

I'm finally catching up with things...starting reseting each tank in Feb when I hit 20,000 miles-

3/6/2007 216.2 mile 4.479 gal 48.2697 MFD showed 43.8......

 

<div class='quotetop'>QUOTE(Tideland Prius @ Mar 9 2007, 03:44 AM) [snapback]402699[/snapback]</div>

Ok. What I don't really understand is the apparently very large discrepancy between calculated mileage and MFD display! Since the purchase of my Prius about a month ago I've filled up two times, with the first saying 5.1L/100km (or 46.11mpg US) and the second saying 5.0L/100km (or 47.04 mpg) on the MFD. But when I calculated the amount of kilometers driven divided by the amount of gas added I get far from these figures. Both times it averaged out to something like 5.5L/100km (or 42.76) and 5.65L/100km ( or 41.62 mpg). Isn't it a bit off to be more than 10% whacky? I've read people saying 2 mpg off, but this seems suspect. Am I really the only one who is finding this big of a gap? Am I math dumb? Or am I missing some basic concept of how to calculate tank mileage?

I do realize that two tanks may not be enough to judge by, but is there anything else that I could take into consideration? And before anyone replies, I do know about filling the tank slowly, and this is perhaps the reason I was able to get in 39 liters the first time and 37 liters the second time.

Thanks to all that take the time to share their experience!

JP

<div class='quotetop'>QUOTE(Great White North @ Mar 12 2007, 10:47 PM) [snapback]404576[/snapback]</div>

...and then of course I look back at Tidelands figures and realize that he is 10% off with the 4.6 to 5.04 gap as well. So...um...is it only us two then? (he added sheepishly...)

 

<div class='quotetop'>QUOTE(Tideland Prius @ Mar 13 2007, 01:47 AM) [snapback]404702[/snapback]</div>

Wow. My first "pip"/bar hasn't disappeared yet for this tank and I'm at 157km. These things are really inconsistent. Still love the car though.
And yes, I didn't really consider the fact that the bladder could hold more fuel with the warmer temperatures. This was the information I was looking for. Thx again.

 

I'm averaging about 5.3 L/100km for March. We had weather down to -20C for a week or so. I blocked the front with pipe insulation (2 stripes on the top and 2 on the bottom) so I didn't notice when the temp dropped from -10C to -20C. I've only done 4 fill-ups though, having an odometer reading of 2700km. I'm only able to fit around 32L of gas once the last bar starts to blink.



I hope it picks up in the good weather. I'm not anywhere near the 'official' consumption.

 

<_< For over 2½ years, I have kept "tank by tank" records on my original '04 Prius and now my '07 touring Edition. I have found that the MFD is more than 98% accurate when compared to the pumped fuel/miles traveled. A single tank comparison cannot provide an accurate result. My accuracy is over MANY fuelings.

>98% is "close enough for government work" for me.

 

It's warming up here-

happy days!

 

<div class='quotetop'>QUOTE(barbaram @ Apr 2 2007, 03:40 PM) [snapback]416547[/snapback]</div>

And here:



This was about 10 days ago. I filled up last Wednesday after about another 100 miles, 65.2 MPG (calculated) for the tank.

 

<div class='quotetop'>QUOTE(Tideland Prius @ Apr 3 2007, 12:25 AM) [snapback]416827[/snapback]</div>

Yeah, but I suspect you'll be happily cruising along without AC in mid-July, won't you? I'll be trying to cruise without AC then, but it won't be happily!

 

Miles 1402.4
Gal 30.7720
MPG 45.57389835

MFD low 43.1 to high 49.7