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I noticed that my cars gas gage is not linear meaning that the first half tank I get about 200 miles on it and the second half I only get about 100 - 150. This is pretty consistent in the first 7000 miles I've put on it.

I know it's not related to the extra gas beyond the red zone as I've put in 18.5 gallons before.

Has anybody else noticed this?
 

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Pretty much every car I've ever owned in my entire life has shown a non-linear gage travel, with the exception of my 1998 WS6. GM even made a big deal about it back in 1998... and then subsequently f***ed it all up when they switched to a slightly bigger plastic fuel tank in 1999+. :lol:
 

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Yep - as has been said - this is normal on almost all cars. It's due to the float mechanism in the tank and the variation in the angle. As the fuel goes below half way, the float moves more degrees per unit fuel taken from the tank - this gets worse the lower the fuel gets.

In other words (and for example):

The float moves 10 Deg per gallon used when full
The float moves 12 Deg per gallon used at 3/4
The float moves 15 Deg per gallon used at 1/2
The float moves 20 Deg per gallon used at 1/4

Made up figures, but the trend is the same. :)
 

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yea and cars that have more of an angled fuel pump, like neons/ focus's dont seem to be as bad.
 

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Yep - as has been said - this is normal on almost all cars. It's due to the float mechanism in the tank and the variation in the angle. As the fuel goes below half way, the float moves more degrees per unit fuel taken from the tank - this gets worse the lower the fuel gets.

In other words (and for example):

The float moves 10 Deg per gallon used when full
The float moves 12 Deg per gallon used at 3/4
The float moves 15 Deg per gallon used at 1/2
The float moves 20 Deg per gallon used at 1/4

Made up figures, but the trend is the same. :)
Hmmmmmmm

Ya got me thinking now. Because what the OP described is counter-intuitive. You would expect to get better gas mileage from the second half of the tank, because you're moving less weight, but this angle thing makes sense. I used to argue with my ex-wife's cousin all the time about this; he swore he got more mileage from the first half of the tank. But I always told him that was impossible. Maybe he was correct afterall. Mr Flexy wrong??? How can that be??? UGH!

Personally I never pay attention to mileage, though. I couldn't care less...

-=FLEX=-
 

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The argument about better mileage on the first "half" tank is invalid, because the halfway mark isn't really the halfway mark.
 

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The argument about better mileage on the first "half" tank is invalid, because the halfway mark isn't really the halfway mark.
So I was right then?

Whew! :)

That's good, cuz

1) I hate being wrong, and
2) I never liked my ex-wife's cousin.

:lol:
 

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Hmmmmmmm

Ya got me thinking now. Because what the OP described is counter-intuitive. You would expect to get better gas mileage from the second half of the tank, because you're moving less weight, but this angle thing makes sense. I used to argue with my ex-wife's cousin all the time about this; he swore he got more mileage from the first half of the tank. But I always told him that was impossible. Maybe he was correct afterall. Mr Flexy wrong??? How can that be??? UGH!

Personally I never pay attention to mileage, though. I couldn't care less...

-=FLEX=-
:)

Fuel usage (or miles per unit fuel used) is a function of the driving style and conditions. The 'report' of what is being used is the thing that gets screwed up!
 

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:)

Fuel usage (or miles per unit fuel used) is a function of the driving style and conditions. The 'report' of what is being used is the thing that gets screwed up!
I understand. But, ALL OTHER CONDITIONS BEING EQUAL (an admittedly unlikely scenario) any vehicle would use less fuel per mile on the second 'half' of the tank, because less mass is being moved.

Again, I don't give a rats arse about fuel economy, as proven by:
1) my driving style and
2) the rather long list of V8 automobiles I have personally owned - 1980 Chrysler Newport (first car), Three different 5.0L Mustangs ('87, '88, '91), two Corvettes ('80 & '90), a Lincoln Mark VII LSC, a 2006 Impala SS, and now my beloved Charger R/T.

:)
 

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I understand. But, ALL OTHER CONDITIONS BEING EQUAL (an admittedly unlikely scenario) any vehicle would use less fuel per mile on the second 'half' of the tank, because less mass is being moved.
As I like to say, there's always more than meets the eye in any scenario...

In the above case of less fuel in tank, there's more empty "space" into which the remaining liquid fuel can evaporate, and this isn't going to make its way to the engine. A full tank will keep more of its fuel in liquid state longer. So that would tend to support the fuel mileage argument of the top half. Enough to offset the mass reduction? Don't know, but it just proves that real-life physics is not uni-dimensional.
 

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I understand. But, ALL OTHER CONDITIONS BEING EQUAL (an admittedly unlikely scenario) any vehicle would use less fuel per mile on the second 'half' of the tank, because less mass is being moved.

Again, I don't give a rats arse about fuel economy, as proven by:
1) my driving style and
2) the rather long list of V8 automobiles I have personally owned - 1980 Chrysler Newport (first car), Three different 5.0L Mustangs ('87, '88, '91), two Corvettes ('80 & '90), a Lincoln Mark VII LSC, a 2006 Impala SS, and now my beloved Charger R/T.

:)
Yes - technically and in perfectly controlled conditions you would expect to use less fuel as a vehicle reduced in weight.

However, for steady state driving, the function of drag is the killer for steady state speed (and even that isn't too bad below, say, 70mph). If you are not accelerating a vehicle, then its weight isn't that much of a deal (compare a 2,000kg (gas empty) vehicle to a 2,050kg (gas full) vehicle). The only potentially bigger drain would be the pressure of the tyres on the pavement (increased rolling resistance with greater load), increased friction within the wheelbearings (greater loading), increased friction in any other bearings (due to load increase) and increased friction on gear faces (which would result in the gears running a little hotter = more energy lost as heat). Now - if you want to accelerate this puppy, it helps to be lighter, as the reduced inertia saps less power/energy.

Kinda.... :nervous s
 

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Yes - technically and in perfectly controlled conditions you would expect to use less fuel as a vehicle reduced in weight.

However, for steady state driving, the function of drag is the killer for steady state speed (and even that isn't too bad below, say, 70mph). If you are not accelerating a vehicle, then its weight isn't that much of a deal (compare a 2,000kg (gas empty) vehicle to a 2,050kg (gas full) vehicle). The only potentially bigger drain would be the pressure of the tyres on the pavement (increased rolling resistance with greater load), increased friction within the wheelbearings (greater loading), increased friction in any other bearings (due to load increase) and increased friction on gear faces (which would result in the gears running a little hotter = more energy lost as heat). Now - if you want to acceperate this puppy, it helps to be lighter, as the reduced inertia saps less power/energy.

Kinda.... :nervous s

[email protected] dude your smart!!! <saves thread post so he can seem smart when this comes up again in 2 months>:)
 

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Yes - technically and in perfectly controlled conditions you would expect to use less fuel as a vehicle reduced in weight.

However, for steady state driving, the function of drag is the killer for steady state speed (and even that isn't too bad below, say, 70mph). If you are not accelerating a vehicle, then its weight isn't that much of a deal (compare a 2,000kg (gas empty) vehicle to a 2,050kg (gas full) vehicle). The only potentially bigger drain would be the pressure of the tyres on the pavement (increased rolling resistance with greater load), increased friction within the wheelbearings (greater loading), increased friction in any other bearings (due to load increase) and increased friction on gear faces (which would result in the gears running a little hotter = more energy lost as heat). Now - if you want to accelerate this puppy, it helps to be lighter, as the reduced inertia saps less power/energy.

Kinda.... :nervous s
I'm a city boy. I had assumed low speed 'stop-and-go' driving conditions, in which case weight would play a more significant factor than drag on fuel consumption. ;-)
 

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I'm a city boy. I had assumed low speed 'stop-and-go' driving conditions, in which case weight would play a more significant factor than drag on fuel consumption. ;-)
I'm not playin' anymore..... :grin:


But, yes - stop and go would be worse....unless you consider the inertia of the extra fuel allowing you to be able to coast longer as you approach a stationary position..... The extra energy stored in the fuel allows for a slightly longer coast.... :p
 

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I'm not playin' anymore..... :grin:


But, yes - stop and go would be worse....unless you consider the inertia of the extra fuel allowing you to be able to coast longer as you approach a stationary position..... The extra energy stored in the fuel allows for a slightly longer coast.... :p
You're killing me. :lol:

But on your way back to the UK, schedule a stopover in Toronto, rent a car for a bit, and see how much 'coasting' you get to do. I'd say not too freaking much. You're always on the gas or the brake up here, my friend.

:(
 

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Heres what i do :p every time i fill up i just put 20 bucks in. dont even look at the gals or the price. taht way i dont know what a full tank just cost me. i run with less fuel = faster and more MPG. i have to make more fill ups but i dont care cuz im always on the road at least once a day.

i justify the money i spend on gas in that.. i work 40 hrs a week and dont spend money on anything but food and gas. maybe a splurge on a car part here and there... a new cd or a bottle of whiskey ;) so the money i spend on gas is my "fun" money. so whats spent there is burned hot and heavy in the name of fun!

ugh. gas is spensive tho
 

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Heres what i do :p every time i fill up i just put 20 bucks in. dont even look at the gals or the price. taht way i dont know what a full tank just cost me. i run with less fuel = faster and more MPG. i have to make more fill ups but i dont care cuz im always on the road at least once a day.

i justify the money i spend on gas in that.. i work 40 hrs a week and dont spend money on anything but food and gas. maybe a splurge on a car part here and there... a new cd or a bottle of whiskey ;) so the money i spend on gas is my "fun" money. so whats spent there is burned hot and heavy in the name of fun!

ugh. gas is spensive tho
I do the opposite. I fill it to the brim, then drive it until it's on empty.

I don't care what I spend on fuel either; the money I spend on gas for the car in a week (about $80) pales in comparison to what I spend on beer a week (*CENSORED*). :)
 

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I do the opposite. I fill it to the brim, then drive it until it's on empty.

I don't care what I spend on fuel either; the money I spend on gas for the car in a week (about $80) pales in comparison to what I spend on beer a week (*CENSORED*). :)
Dude - we mujst be related! :grin:
 

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