Fuel Mileage Computation
09-30-2009, 12:25 PM
#11
5th Gear Member
Join Date: Oct 2005
Location: Southern California
Posts: 3,678
... # of gallons (per the gas station pump)
Hand calculation also assumes that both your odometer and the gas station's pump are accurate. The on-board is good for a relative reading in most cases. Additionally, if you're not hand calculating AND resetting your average MPG at each fill-up, you'll barely see those changes to your fuel economy that indicate something is amiss with the car (i.e., low tire pressure, poor fuel quality, clogged intake filter...).
Hand calculation also assumes that both your odometer and the gas station's pump are accurate. The on-board is good for a relative reading in most cases. Additionally, if you're not hand calculating AND resetting your average MPG at each fill-up, you'll barely see those changes to your fuel economy that indicate something is amiss with the car (i.e., low tire pressure, poor fuel quality, clogged intake filter...).
thats why i dont believe manual calculation is any more accurate than the dash reading. gas pumps vary on how accurate they are in dispersing fuel. i know this whenever i fill up my little red tank for my lawnmower. 2 gallons on the pump display IS NOT 2 gallons in my tank. something is off the mark.
"+" or "-" 1mpg seems to be the margin for error.
10-01-2009, 08:19 PM
#12
Thread Starter
Join Date: Jan 2009
Location: MT
Posts: 28
thats why i dont believe manual calculation is any more accurate than the dash reading. gas pumps vary on how accurate they are in dispersing fuel. i know this whenever i fill up my little red tank for my lawnmower. 2 gallons on the pump display IS NOT 2 gallons in my tank. something is off the mark.
"+" or "-" 1mpg seems to be the margin for error.
"+" or "-" 1mpg seems to be the margin for error.
10-01-2009, 09:33 PM
#14
6th Gear Member
10-02-2009, 08:06 AM
#15
Site Moderator of Fury!
Join Date: Aug 2007
Location: Houston, TX
Posts: 5,104
I get 15 mpg on average. I never look at the computer mpg but maybe once because I don't care what mileage I get, because I know it won't be good 
I do look at my boost gauge all the time though, and I am fairly sure if I could look at my boost gauge and gas gauge at the same time, they move in opposite directions almost simaltaneously.
I do look at my boost gauge all the time though, and I am fairly sure if I could look at my boost gauge and gas gauge at the same time, they move in opposite directions almost simaltaneously.
10-02-2009, 12:50 PM
#16
5th Gear Member
Join Date: Oct 2005
Location: Southern California
Posts: 3,678
I get 15 mpg on average. I never look at the computer mpg but maybe once because I don't care what mileage I get, because I know it won't be good
I do look at my boost gauge all the time though, and I am fairly sure if I could look at my boost gauge and gas gauge at the same time, they move in opposite directions almost simaltaneously.
I do look at my boost gauge all the time though, and I am fairly sure if I could look at my boost gauge and gas gauge at the same time, they move in opposite directions almost simaltaneously.
10-02-2009, 01:01 PM
#17
Gentleman's Relish
Join Date: Feb 2005
Location: AZ
Posts: 13,090
IF it's a Premium model is most certainly has it. It was one of the few available options on the deluxe models.
10-03-2009, 08:59 AM
#18
1st Gear Member
Join Date: May 2009
Location: Maryland
Posts: 90
10-04-2009, 11:25 AM
#20
2nd Gear Member
Join Date: Feb 2009
Location: FL
Posts: 157
thats why i dont believe manual calculation is any more accurate than the dash reading. gas pumps vary on how accurate they are in dispersing fuel. i know this whenever i fill up my little red tank for my lawnmower. 2 gallons on the pump display IS NOT 2 gallons in my tank. something is off the mark.
"+" or "-" 1mpg seems to be the margin for error.
"+" or "-" 1mpg seems to be the margin for error.