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Discussion Starter · #1 ·
How does this calculation work? When I got the car this past summer It read about 395 miles to empty. Yesterday I filled it up and it read 345 mte. Why the big change? I am not sure I filled it last time...so
Does it go by the last fill up?
Do you have to "fill" the tank each time to get a accurate reading?
Does it go by the current mpg calculation?

The mpg calculation is reading high too.
Thanks
 

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How does this calculation work? When I got the car this past summer It read about 395 miles to empty. Yesterday I filled it up and it read 345 mte. Why the big change? I am not sure I filled it last time...so
Does it go by the last fill up?
Do you have to "fill" the tank each time to get a accurate reading?
Does it go by the current mpg calculation?

The mpg calculation is reading high too.
Thanks
Try resetting the MPG calculations and see what happens...
 

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I reset mine every time, seems the more gas it takes to fill the higher the estimated miles to empty (not sure how the calc is done but is pretty darn accurate IMO)
 

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It goes on previous MPG and the fuel level in the tank. It adjusts to your driving conditions but does not directly take the current mpg*gallons of fuel left.
 

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Discussion Starter · #5 ·
I usually reset the trip and mpg monitors when I fill up. (usually around 1/2 tank full) I try to fill until it clicks off at the pump. I thought it was strange it's now about 40-50 miles less than before. Maybe it's the winter gas lowering my mpg?
 

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I usually reset the trip and mpg monitors when I fill up. (usually around 1/2 tank full) I try to fill until it clicks off at the pump. I thought it was strange it's now about 40-50 miles less than before. Maybe it's the winter gas lowering my mpg?
Yep.
 

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I almost never reset my trip computers except the distance ones. It seems that in the 20,000 miles I've owned the car, the average is great enough that I get consistent tank readings whenever I fill up.

Another thing to consider: you're never going to have the same fill each time, even if you use the same pump for each fill up. A number of factors can cause enough variability in each fill trip that the amount you receive could differ by as much as a gallon which would factor significantly into your MTE reading as well.
 

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I have had the "miles to empty" anywhere from 20 to zero while driving in the mountains, with the gauge needle pointing to "E", then when I am back on level road it pops back up to 1/4 tank and the MTE goes back to 60-65. When I fill the car at this point it usually takes 8 or 9 gallons.

Also I have driven many miles on a couple of occasions with the "miles to empty" showing zero.
 

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Miles to empty accuracy....


 

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I have had the "miles to empty" anywhere from 20 to zero while driving in the mountains, with the gauge needle pointing to "E", then when I am back on level road it pops back up to 1/4 tank and the MTE goes back to 60-65. When I fill the car at this point it usually takes 8 or 9 gallons.

Also I have driven many miles on a couple of occasions with the "miles to empty" showing zero.
I have also run as many as 20 miles after the MTE display went to zero and one tank I managed 574 miles before stopping to add a couple gallons from a Gerry can. I had not run out but I knew I had another 45 miles to go to fill up and wouldn't make it.

When I get to zero and refill at that point the refill usually takes about 11.7 gallons. The tank is listed as 12.4 gallon and I usually top off by about 0.4 gallons so I could have as much as a gallon when the MTE goes to zero.


Brian
 

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Silly question, other than maybe doing it once with a new car to see how far you could go in an emergency, why try to run the tank low?

Low tank results in extra condensation (water in the gas) if you do it regularly.

Not good for the fuel pump, between loss of cooling and in extreme cases loosing prime intermittently.

I know some always run on empty, Wife always did and ran out more than once, never could understand it.

Fuel system can't use all the gas in the tank, won't keep running until it's dry, leave a couple gallons or more in there at least.
 

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Silly question, other than maybe doing it once with a new car to see how far you could go in an emergency, why try to run the tank low?

Low tank results in extra condensation (water in the gas) if you do it regularly.

Not good for the fuel pump, between loss of cooling and in extreme cases loosing prime intermittently.

I know some always run on empty, Wife always did and ran out more than once, never could understand it.

Fuel system can't use all the gas in the tank, won't keep running until it's dry, leave a couple gallons or more in there at least.

False economy...

Some people actually believe they save money by going the least often to the gas station...

[facepalm]
 

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Same issue here lately...my ~400 miles to empty I was used to seeing is now in the low-to-mid 300s. Its just the winter temps and fuel combined with slower warm ups...got to be.
 

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Today I started out with 88 "Miles to empty". Partway through my 45 mile commute (winding mountain road) the needle went all the way down and the low fuel light came on. I checked. 32 MTE. Checked a few miles later. 18 MTE. Ten or so more: 3 MTE. Stopped at the signal light after coming out of the mountains: 80 MTE and the needle is up to 1/4 tank. Filled at the nearest station. 9.6 gallons. Kind of glad the whole system is pessimistic though.
 

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Silly question, other than maybe doing it once with a new car to see how far you could go in an emergency, why try to run the tank low?

Low tank results in extra condensation (water in the gas) if you do it regularly.

Not good for the fuel pump, between loss of cooling and in extreme cases loosing prime intermittently.

I know some always run on empty, Wife always did and ran out more than once, never could understand it.

Fuel system can't use all the gas in the tank, won't keep running until it's dry, leave a couple gallons or more in there at least.

If there is anything good about ethanol in gas it is that it tends to remove water before it can accumulate. In fact, the gas treatments designed to remove water use ... wait for it ... ethanol.

No, running your tank down isn't by itself going to get you better gas mileage, however, if you tend to make a trip of getting gas then doing it less often will save a little.

I've run out of gas just once, thankfully I had a gas can with me and was able to make it to a gas station.

Living as I do in the western part of the USA it can be hundreds of miles between gas stations so knowing the limits of your tank is a good idea.


Brian
 

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If there is anything good about ethanol in gas it is that it tends to remove water before it can accumulate. In fact, the gas treatments designed to remove water use ... wait for it ... ethanol.

No, running your tank down isn't by itself going to get you better gas mileage, however, if you tend to make a trip of getting gas then doing it less often will save a little.

I've run out of gas just once, thankfully I had a gas can with me and was able to make it to a gas station.

Living as I do in the western part of the USA it can be hundreds of miles between gas stations so knowing the limits of your tank is a good idea.


Brian

The problem with Ethanol it is highly hygroscopic... means it will literally absorb water (like brake fluid) until its too diluted (and its additives too), cause fuel lines to freeze,hard to start (vaporize when cold), turn rancid and eat every piece in contact with it in long term (see E85 & E100 problems)

That's why they strongly recommend running a complete tank of regular gasoline once in a while...

Ethanol is a marvelous gas but only in controlled conditions...
 

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Not trying to find the limits or to save money. Just trying to get to work and the next fuel fill.

OP asked what other owners' experience with the 'miles to empty' feature is and I just described my experience and observations.
 

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It's good to share experiences with how that tool (toy in some folks opinion) works so it can be used to best advantage.

It can give a decent running estimate that in many circumstances can be useful. Knowing the limits & exceptions to that ability helps in using it.

Old School use of a trip odometer & your own knowledge of typical MPG for the type of driving done - matched with instrument readings for a double check - is still the best estimate you can get IMHO.
 

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It's good to share experiences with how that tool (toy in some folks opinion) works so it can be used to best advantage.

It can give a decent running estimate that in many circumstances can be useful. Knowing the limits & exceptions to that ability helps in using it.

Old School use of a trip odometer & your own knowledge of typical MPG for the type of driving done - matched with instrument readings for a double check - is still the best estimate you can get IMHO.
Yep. When it gets close to empty, fill it.
 
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