Who Calculates/ How is MPG Calculated?

[Nick1994]

Originally Posted By: Kira
Hello, To Nick1994: In your Jeep Cherokee example you said, "calculation compensated for tire size".
How'd you do that?

FOI: (For Our Information)
I simply start with a fill up and note the miles on the ODO.
I make sure to fill up at month's end and note the ODO.
Add up all fuel purchases. The total=GALLONS.
Subtract the starting mileage from the ending mileage. The result=MILES.
MILES/GALLONS=mpg.

Here's comes the part where I'll get scolded for flaming.
On board computers are really only good for "on the fly" notation.
It's so simple to calculate accurate mileage. People should just do that.

The methods employed by auto makers and/or a government agency are going to be negotiated with "results" having to fit a marketing profile. Kira
With the Jeep since it has larger tires I used Google Maps and Apple Maps to double check the miles between where we filled up and where we filled up next and divided the amount of gallons used.

 

[Nick1994]

Last summer my brother followed me in my 97' Camry and he was in the 96' Lexus from Montana to Arizona. We were both at 80 mph and consistently got 28-29 mpg in the Lexus and 33 mpg in the Camry. And I mean this was pedal to the floor in the hills (lots of mountains between Montana and AZ), I couldn't push it any harder. Also using A/C.

 

[ARCOgraphite]

I'm not happy at all with the 14 rogue, after the OCI#1 it only averaging 19MPG! I usually beat the EPA highway rating in my mixed driving. Whassup here? IS the winter blend super nasty this year with lots of low energy, upper volatiles in the blend?
Aslo I don't think this older gen CVT is conducive to good MPG numbers.
Otherwize I like it as a 1 person driver over a Subaru for general comfort and serene ride - and Im a long time Subaru guy. If you are looking for packaging, room and mileage the base 6MT Forester is WAY better. The Wife is averaging 28mpg even with the harsh winter.

 

[supton]

What is the EPA rating on the Rogue?

It's been darn cold, and slippery to boot. Last summer I got three tanks of 21.7mpg in my truck--followed by 22mpg!--but right now it's hovering at 16.5mph. Winter gas, 4x4 usage, snow tires. In your case I'd guess winter gas and stupid cold weather is to blame--but it's also a new vehicle, no? Give it a few tanks, pump up the tires and wait for the spring thaw. It's right around the corner, only another 3 months left to go.

 

[geeman789]

Some transportation think tank recently proposed removing the mpg number completely, and replacing it with a letter grade scale. Cars / trucks would be tested, then given a letter score. "A" if car exceeded xx mpg, "B" if car was between xx and xx. mpg, and "C" if car was below xx. mpg.

The reasoning was that common phrase "your mileage may vary..." . Instead of putting a hard number on a car, they hoped that grouping cars into similar classes might eliminate the complaints about exact mileage. Nothing ever happened..

Also risky is the xx miles per tankful used by some car makers... you put an exact number on something, and people will judge strictly based on that number.

My mileage complaint is this... I live in Canada. I have NEVER bought a gallon of gas, not have I driven a single mile. We use metric, we buy liters of gas, and our roads and speedometers / odometers are in kilometers. For the last 30 years or more...

Yet, our canadian car / truck marketing always promotes miles per gallon. And "our..." gallon is an imperial gallon, so you can't even compare it to a US MPG claims...

I guess to somebody 40 mpg ( per imperial gallon...33 mpg per US gallon) just sounds better than 7 liters per 100 km ...

I like the liters per 100 km , less gas is better, so a smaller number is better..

I have friends though that will still convert from L / 100 km back to MPG, because they don't "get..." the metric number.... after 30 years....?

 

[Quattro Pete]

Originally Posted By: geeman789
I guess to somebody 40 mpg ( per imperial gallon...33 mpg per US gallon) just sounds better than 7 liters per 100 km ...

I like the liters per 100 km , less gas is better, so a smaller number is better..

They started putting gallons / 100 miles on vehicle window stickers here, but it's in small font and I guess most people don't pay attention to it. I don't expect the general population to convert to a different way of measuring fuel consumption anytime soon.

 

[horse123]

Originally Posted By: supton
What is the EPA rating on the Rogue?

It's been darn cold, and slippery to boot. Last summer I got three tanks of 21.7mpg in my truck--followed by 22mpg!--but right now it's hovering at 16.5mph. Winter gas, 4x4 usage, snow tires. In your case I'd guess winter gas and stupid cold weather is to blame--but it's also a new vehicle, no? Give it a few tanks, pump up the tires and wait for the spring thaw. It's right around the corner, only another 3 months left to go.


How often do you use 4wd? The only time you should use it is when you're stuck, it's monumentally wasteful on gas and eventually maintenance costs to use it all the time.

 

[datech]

As far as actual MPG the DIC in my Cobalt and the Scangauge II I use in my SUV usually came pretty close to the calculated MPG the few times I have actually gone to the trouble.

What I llke about the Instantaneous MPG readout is how I can use it to drive more efficiently and also it might alert me to a mechanical problem, like dragging brakes, etc.

How the numbers compare with the EPA mpg ratings does depend a lot on the driving environment for that particular time and place.

 

[supton]

Originally Posted By: horse123
How often do you use 4wd? The only time you should use it is when you're stuck, it's monumentally wasteful on gas and eventually maintenance costs to use it all the time.


It's actually kinda nice to keep from getting stuck in the first place. You know, like when the rear of the truck keeps kicking out because you're on several inches of snow. Or you're looking up the hill and there is a foot of snow on it.

Right now I'd say I'm using it about a quarter of the time, give or take. I drive my car on nice days, which is most of the time. When it snows I take my truck. Ergo, it is seeing "lots" of 4x4 usage. Mind you, despite 16mpg and a tiny 20gallon tank, I'm filling it maybe every other week.

Since it's an old-school part time system I don't use it on bare or wet pavement. Pretty much only when it's pretty slippery, whenever RWD isn't getting it done. And yes, I have snow tires on it.

 

[MNgopher]

The manufacturers run the test to the EPA spec. The spec controls just about anything you can think of, including the fuel, so it is the same as any other car.

Thus, the only real comparison one can make is a relative comparison between cars.

Your actual mileage will vary (and sometimes considerably). Your drive doesn't use the same gas, at the same temp, with the same throttle settings, etc...

 

[Vikas]

OP: Brag Thread!

 

[Quattro Pete]

Originally Posted By: Vikas
OP: Brag Thread!

LOL!

Was kind of thinking the same thing.

 

[Nick1994]

Originally Posted By: Quattro Pete
Originally Posted By: Vikas
OP: Brag Thread!

LOL!

Was kind of thinking the same thing.
Brag thread? What's there to brag about? Old beater cars getting better than what the manufacturer says they will? The good mpg's posted are when driven gently at 65 mph. The Trailblazer gets 16-17 mpg on average for my grandparents since it's short tripped, the Jeep gets like 15 mpg, my Camry got 23 mpg commuting, and the Lexus gets maybe 18 mpg. Other cars in my family don't exceed the ratings such as my dad's FJ Cruiser, it gets like 17 mpg max. My step moms Pontiac G6 gets 30 mpg max and my truck used to get 14-15 mpg commuting, and 17 mpg max on the freeway.

 

[dlundblad]

I can see where they are getting at Nick. The Lexus that burns 1 quart in less than 1000 miles is definitely brag worthy.

 

[Nick1994]

Originally Posted By: dlundblad
I can see where they are getting at Nick. The Lexus that burns 1 quart in less than 1000 miles is definitely brag worthy.

Oh yeah, that thing sure is a fine specimin of an automobile. Even 10w40 MaxLife burns at 400-500 miles per quart. Every startup is a nice smoke cloud. The peeling paint too is a nice touch.

What's actually hilarious about this car, is my brother bought it from a guy who buys cars from an auction. The Lexus was previously used to smuggle illegal immigrants across the border from Mexico. It's emblems were missing, the rear struts had homemade spacers so it would ride level when loaded down, and the back seat was missing to allow more people to fit when stacked on top of each other LOL!

 

[dlundblad]

How did it smell when he bought it? Lol.

 

[Nick1994]

Originally Posted By: dlundblad
How did it smell when he bought it? Lol.
Lol it didn't smell too bad, the guy cleaned it up pretty good. Had weird issues with the car though. Check engine light comes on for an Evap code or something, the drivers power seat switches didn't work. Like it was removed probably by the cops during searching the car, the cd changer in the trunk was missing, emblems were missing, antenna broke off, and the windows had a weird coating on the inside so it was hard to see in. All in all it was pretty cheap and the engine runs great besides the oil burning.

 

[SHOZ]

Both my cars beat the EPA average by quite a bit usually. I use my Garmin to get the correction for the factory ODO. Then just calculate by hand. You cannot go n=by the onboard display I have found.

40-42 mpg on a '08 Hyundai Accent using 87 E10, 30 mpg on a 2010 Hyundai Genesis Coupe 2L turbo using 92 E10.

 

[oliveoil]

I've been calculating using miles driven by gallons (first click) for most of my life.

 

[supton]

I keep a log book in each vehicle miles and gallons get filled in each time. Eventually it gets transferred to Excel.

The Jetta is pretty cool. I've always filled it to the brim for max distance, and hopefully repeatable fills. Oddly, it's best mpg has always been in winter.