Best Mileage?

On Wed, 16 May 2007 17:20:26 -0400, "Roy" <Roy.RemoveThis@Fhome.net> wrote:

>They are deadly accurate.


Deadly is not a term i would use. They are as accurate the calibration
of the fuel metering system of vehicle and like anything there is
production tolerance and some with be mostly on and some will be off
some. Also since it is relative to speedo accuracy as well until they
all use GPS for speed and distance verification (and it is indeed
deadly accurate) it will never be right one unless your car is a
fluke. (change your tire size and accuracy can go right out the
window)
-----------------
TheSnoMan.com
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"SnoMan" <admin.DeleteThis@snoman.com> wrote in message
news:9mvm43dogr0o9gnsc0d20sh9q6cf0hnkre@4ax.com...
> On Wed, 16 May 2007 17:20:26 -0400, "Roy" <Roy.DeleteThis@Fhome.net> wrote:
>
>>They are deadly accurate.
>
>
> Deadly is not a term i would use. They are as accurate the calibration
> of the fuel metering system of vehicle and like anything there is
> production tolerance and some with be mostly on and some will be off
> some. Also since it is relative to speedo accuracy as well until they
> all use GPS for speed and distance verification (and it is indeed
> deadly accurate) it will never be right one unless your car is a
> fluke. (change your tire size and accuracy can go right out the
> window)
> -----------------
> TheSnoMan.com


Idiot that was a goof! Everybody who owns a Dodge know's they are not at all
accurate. But wait a sec, you don't own a Dodge.
 >> Stay informed about: Best Mileage? 

>I have a '06 2500 Cummins. Overhead, there's a mileage indicator. This
>trip, on a downhill run, it got up to 43.3 mpg. Just how accurate are
>those overhead indicators?

That was either an instantaneous reading (some years have both average
economy and instant economy displays), or you had just reset it. But - at
that point in time, with you running downhill, you probably were getting
43MPG.

If everything is left stock (tires, wheels, fuel system), I'd say the
overhead is accurate to within 5% or so, as long as you've got over 100
miles since it's last reset (again, different model years use different
algorithms to average fuel economy).
 >> Stay informed about: Best Mileage? 

My '99 Ram gas burner shows about 10% higher than actual MPG. That also
means that the Distance To Empty (DTE) is off by about the same. I
regularly check the odometer by comparing it to highway mileage marks, which
is within 1%.

"Steve B" <ExSurDO2Diver.DeleteThis@Neptune.com> wrote in message
news:d4K2i.310855$g24.129034@newsfe12.phx...
>I have a '06 2500 Cummins. Overhead, there's a mileage indicator. This
>trip, on a downhill run, it got up to 43.3 mpg. Just how accurate are
>those overhead indicators?
>
> Steve
>
 >> Stay informed about: Best Mileage? 

HammerTime wrote:
> Actually, mine is accurate to within about .7 mpg.

I've never read anything about why the computer is inaccurate, but I
would imagine that it is because it takes an average of an average, a
mathematical no-no. So, the inaccuracy could go either direction
depending what the driving style is since last Reset.

Craig C.
 >> Stay informed about: Best Mileage?