tboucher

I just filled up for the first time after driving 318 miles. This cost me $31.52 which compared to the last car was a shocker (lower wise, was paying $45 - 50 for 93 octane which was required)

Obviously the first tank on a new car it's gonna take it a bit for me to settle down wanting to rip it up when I take off some times, but after a while what is everyone averaging?

ScottRNelson

I only have about 800 miles on my car and I drive top down as much as possible, so that doesn't help the economy, but I'm seeing mid-20's so far out on the highway. The only way to really know what mileage you're getting is to keep track of how much gas you put in and how far you drive, then divide the miles by the gallons. Miles per tank doesn't mean much.

And while we're on this subject, it seems that when the gas gauge hits the lowest empty point, there's less than a gallon left in there. I put 15.1 gallons into the 16 gallon tank when I was checking this. I'll fill up when the low fuel light first comes on from now on.

ChristopherCamel

doing it by miles per gallon isnt always true...if for example i drive 20miles on a gallon on highway...if your sitting in traffic or stop and go..it can be lower like 10 or 11 maybe

ScottRNelson

Unless you have a trip computer that tells you instantaneous mileage, the only objective way to figure mileage is by measuring. When you're stopped in traffic, your mpg is zero. All you can do is get an average over a longer period of time.

So I've measured with my car and I've seen 23 and 25 on the two full tanks that I kept track of. Anybody else have any actual numbers?

flapjack

Trip computers are wildly inaccurate, in my experience.

ScottRNelson

So what cars have you experienced them on?

Of the 20 cars I've owned so far, only one had a trip computer, a 1987 Ford Taurus. That one was quite accurate for the mpg computations. I thought the instantaneous mpg was especially interesting, since you could look at that and immediately figure out the most economical way to drive it. I still remember one single-day trip to Yosemite in that car and trying to see if I could get the trip average fuel economy up to 30. I think I got up into the high 28 range by being gentle on the throttle all the way back. Comparing fuel put back in the tank with miles travelled showed that the trip mileage was good.

The only time I would say the trip computer was "wildly inaccurate" was while coasting, which sends the instantaneous fuel economy up to the maximum displayable until you get back on the gas again.

JGB_V6_05

Hey all you have to do is hit the reset button above the radio and it will reset your mpg and you can see how much you mpg youare getting at the time! I have done it many times, around 30 on the interstate

tboucher

Uhm, isn't that what I did by using 318 miles and how much I filled it back up? I have a little program on my Palm T3 that I put in every gas tank/odometer reading and it'll develop a running average for me after a few fills, but if I started at full, drove 318 miles, and then isn't that the same as what you just said?

ScottRNelson

Sorry, I guess I misunderstood your note. I didn't see anything about how many gallons you put in or what your computed mileage was.

So how many miles per gallon are you getting, anyway?

T.J. King

On a daily basis I average 27. However, I don't do much stop and go. I've had a high average for a 1500 mile trip of 31.6. Worst was 24.3 playing on a real twisty road.