[melgish]

This is an easy one... You started with half a tank.

More than likely the pump shut off early, and left you a few gallons shy of a tank full.

 

[melgish]

Regardless, my assumption that I could computationally determine when I needed to fill (12 G x 48.2 = 578miles - buffer 50 M = 528) was wrong and I wanted to provide a heads up to anyone else who might be trying the same.

I wouldn't say your assumption was wrong, you just need to start with known figure. Base your assumption on the amount of fuel poured into the tank, and not the tank's size...

 

[melgish]

Variance between MFD and Pump

I setup my spreadsheet to keep track of the variance between fill-up and mfd and after 12 tanks

The MFD has indicated lower fuel use 8 times, once by as much as .9 gal.
The MFD has indicated higher fuel use 4 times, once by as much as .5 gal.

The average error is .22 gallons more fuel added to tank then MFD indicates as used. This is roughly 2.8%

 

[melgish]

Well, my tires were at 40/42 (doh! I fixed that today) so I should see less of a difference, not more right?

 

[melgish]

What junk?

Fuel is filtered when it's refined. It's filtered as it's put into the tanker truck. It's filtered as it's put into the underground tank, and it's filtered as it's put into your gas tank.

With all these filters, just how much junk could be left?

 

[melgish]

I can't believe all the conversation on running out of gas. How many "absent minded professors" have bought these cars? I don't know of, or even heard of anyone I know who has run out of gas with their cars in the past fifty years. "You have to develop a "system" just cause the thing gets fifty mpg???

It beats working.

 

[melgish]

True enough, or there wouldn't be a filter. But I question the belief that whatever's left sits in some magical pocket in the gas tank that's only accessed when the tank runs dry, or would be of such overpowering quantity that it would immediately clog the last bastian of fuel cleansing before the injectors.

 

[melgish]

Well, I'm fixin to run out of gas today. I hit the 3rd pip on the guage somewhere between 405 and 410 miles

Currently: 448.6 on the odo, 52.6 mpg on the mfd

MFD Average is 49.2, Tank Average is 47.8 over 13 tanks.

The math says I got from 75 to 130 miles left.
It's 75 miles to get home, but I can refuel at 50.

Murphy insists I'll run out before I get to 50.

 

[melgish]

I drove to work today I know, I know, it was a stupid thing to do.

Actually, I'm farily convinced I can make it all the way back to Melbourne.
Unfortunately once I get on the Bee-Line refuling options are non-existant for about 30 miles, hence a bit of aprehension.

It's a gamble, and an unnecessary one, I'll admit... But until I do, I won't know for sure, and that will eat at me until I go sane.

 

[melgish]

To be continued...

We are on the edges of our seats!

Then I won't keep you in suspense any longer.

Made it all the way home with two pips still aglow.
ODO: 523.7 Miles
MFD: 52.7 MPG
10.179 to fill tank.

Just in time to flee the wrath of Jeanne, but I guess we're waiting for the 11:00 PM report before we load up.