Tank level when you refill?
 

At what point on the gas gauge do you guys refill? Does this have any noticeable impact on FE numbers? I've been refuelling at 1/2 tank because I always like to have plenty for an emergency, but I'm wondering if the extra weight or more frequent fillups will hurt long term averages?

I wait until the last minute... When the SG says I have less than 40 miles to go (a few times hitting 10). I can feel the difference after fill up, my acceleration feels more laggy. And this makes sense considering the weight of 15 gallons of fuel :p So, if the butt-o-meter feels a difference, I'm willing to bet there's an FE difference (probably minor when looking at the big picture).

I fill up when I have 2 gallons or so left in the tank.

I almost always fill when it is at the 1/8 mark or lower.

Sounds about right. I find that most of my fillups these days technically have 2-3 gallons left. OTOH that still is often noticeably more than 400 miles these days. :)

There are a few reason for this:

1) After going "too far" and running out of fuel earlier this year, I don't want to repeat the experience.

2) I don't have any instrumentation that gives a detailed idea of gas used and gas remaining (for example, my car is too old to use a ScanGauge). I do have my stock gas gauge, but that's a pretty crude read. And while my trip odometer is more accurate, it's only an approximate idea of gas remaining (because it depends upon what I'm currently getting for MPG).

3) Seems I don't have a "gas low" light either. I found that out the hard way when I ran out of gas this year. :( So I don't really have a good idea when I'm "close" to being out. The closest I can get to that is looking at the gas gauge, and it's hard to tell (on that gauge) the difference between 2 gallons left and 2 ounces left...

4) Gas in my tank seems to slosh about (apparently the CRX doesn't have a lot of baffles to keep the gas in one place). As a result, climbing hills, going around corners, etc, can cause temporary fuel starvation (and therefore momentary loss of power) when the tank is really low. I've experienced that temporary loss of power, and I really didn't like the experience.

Of course, if I had very accurate instrumentation to tell me "how far I had left", I might cut it closer occasionally (especially if/when I knew how far away the gas station was). But as it is, I would rather be overly conservative about when I fill up, than go "too far" again. Even so, I've started getting used to going 400+ miles between fill ups (which ain't bad, since I usually put in less than 10 gallons when I do fill up).

BTW:
Yes, I know my garage entry is way out of date. Maybe at some point I'll get around to putting more recent log entries in (from the log book I keep in the car). However, since the wife and I are going on vacation later this week, don't hold your breath about it getting updated anytime this month...

I usually fill the tank when the needle as touched the "red zone". I have, however, filled the tank with the needle below the red zone... And I don't pretend to do that again...!

I had a similar problem, DracoFelis and the needle still moves everytime I turn, climb or go down.

I go by the low fuel light. I might push it this time to make a 400 mile tank though.

jandree22 -

I fill-up at the 1/4 mark and fill to the 3/4 mark, the way I have done all my life.

But don't do it my way! My way means ignoring the tank MPG and only looking at the 90 day average for real MPG (because it reduces the tank-to-tank error).

Warning : For some gas tanks (may or may not be true for you), the gas is used as a lubricant (for the fuel pump?), so you shouldn't run the tank dry. I think 1/8 tank is a good rule unless your gas stations are few and far between.

CarloSW2

There is that and the fuel pump sucking in all the gunk that has settled at the bottom of the tank. If you have a vehicle with a serviceable fuel filter its probably not that big of a deal, but those with so called "life time" fuel filters, the filter media isn't as adept at filtering junk. Atleast this is so on my TJ.

that and the gas is the coolant for the fuel pump. also all the gunk just doesnt clog up the fuel filter it also clogs up the pump itself. either way a new fuel sending unit is quite costly. i fill up before 1/4 tank. i hate spending $40 or so refueling from there so i usualyl go about half. where its around $30 or less