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this is the first car where the full marker is at full but the 3/4 full marker isnt really 3/4 neither is the 1/4 full marker. the way i see it when i look at it - full is full, at the 3/4 full mark its probably 7/8 full, at the half full mark its 1/2 full but when it gets to the 1/4 full mark its gotta be more like 1/8. am i right or am i reading the guage wrong. the 3/4 and 1/4 mark are definately smaller than the middle 2 quarters of the tank, why didn't they make all 4 quarters equal???
 

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That's a topic I've talked about before. When you're tank is full, you'll notice the needle goes past the "full" line. I'd say the full line isn't actually full, more like 1/8 and the 1/4 mark is actually a 1/4. On the same token, the "empty" line isn't really empty either... more like 1/8 of a tank remaining.
 

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How big are the tanks??? When Im riding right on E I can ALMOST get 12 gallons in the tank.

From what Ive noticed, the first half of the gauge is actually about 3/5ths of the total gas in the tank... once it gets below half full, mine seems to shoot to E.
 

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[quote author=rcrooks link=topic=71196.msg1250847#msg1250847 date=1173150420]
How big are the tanks??? When Im riding right on E I can ALMOST get 12 gallons in the tank.

From what Ive noticed, the first half of the gauge is actually about 3/5ths of the total gas in the tank... once it gets below half full, mine seems to shoot to E.
[/quote]

My wife seems to be experiencing the same thing, looks like by the time she gets home tonight the gauge will be slightly less than 1/4 with only about 300 miles on the tank.
 

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the fuel level sensor is linear, while the odd shape of the gas tank means that the volume is not linear in respect to fuel level, which is why the fuel gauge is never perfect.

we all get between 30-60 miles one the fuel light goes on....

i can see this being merged with the old thread very soon...lol
 

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I can't think of a single car I've ever driven where the fuel gauge was very accurate.

However, I think manufacturers are intentionally conservative on the "E" mark just to encourage people to fill up before they really are out of gas.
 

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yupper. ^^
it wouldn't make sense to turn on the light after it's too late to get to a gas station.
 

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Yes, the shape of the gas tank probably determines where the 1/4 lines are. Most cars I have driven seem to be able to go further on the first half than the second half, but this is because you can't use all the fuel in the tank. Most vehicles have 2 or 3 gallons reserve when the fuel light comes on, but you should never use all the fuel in your tank because there always has to be some extra to allow for sloshing while turning, going up or down hill, etc. So really you will never use that last 1/2 to 1 gallon of fuel.

Say the tank is 14 gallons, if the light came on at 3 gallons remaining (from the 14) you would have 11 gallons when the light came on, this is often the point when it feels like you are running out of gas. The half line is set at 7 gallons. This means that the first half (7 gallons) will seem like a lot more gas than the second "half" (seems like 4 gallons). That is always why the tank seems to drop slower for the first half than the second half. It really drops about the same, it just doesn't feel like it since you don't run the car empty.

What they should do, is set the half point halfway between where the light turns on and the full tank, this would make it feel like it drops more linearly. This would also make it feel like once the light was on you are running in reserve. My 318ti does this, I think. It specifies the tank is 13.7 gallons, but I have put exactly that in it on a couple of occasions. I think it specifies the usable range and not the actual tank capacity. I have tested the Mazda and each tick on the gas gauge is the same, I don't notice that it drops any faster below the half line than above. On the highway I get about 15 miles per tick, depending on my throttle and wind, etc.
 

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I was going to start a thread about this a year ago, but forgot, thanks for backing me up.

I always wondered about those lines.
 

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Like I keep telling my wife: When the fuel gauge reads 1/2 full, fill it back up. Problem solved. It is far cheaper to fill the tank from half than it is when it is empty, plus you don't have to worry about needing gas in sketchy parts of town.

Besides, if you have ever had a car stop running due to lack of fuel, even though the gauge tells you there is more than 1/4 tank the you will start keeping gas in it. I learned my lesson.
 

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all yer doing is spending twice as much time at gas stations as you need to but I wouldn't want to get stuck in Houston without gas either (too hot, too many sketchy areas).

I wish the gas tanks were bigger in this car. At 25 MPG (2.5 Auto) you have to run it down to E to get 300 miles out of it. It would be nice if the tank were a few gallons bigger.
 

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unless you anticipate a police chase, i see no reason to haul around a full load of gas all the time, especially if you drive a lot of stop and go, or up and down hills.

i fill up when the light goes on, because i know i have another 60 miles.
if i'm on a trip, i'd stay filled up at least half way if possible, in case i get my ass lost.

i'll fill up earlier if i see cheap-good gas.
 

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not if E is in Santa Barbara when you could have filled up in the OC...

not if E is 120 miles from the next gas station...

not if E happens when you have a bet on who can last the longest in a high speed car chase....

not if E happens when it's raining....

not if E happens when you're already late....
 

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[quote author=alecshawn link=topic=71196.msg1261853#msg1261853 date=1173660274]
Well, F means full. E means empty...When it gets close to the E fill it up. :? Thats not too tough... :screwy:
[/quote]

Sorry, but

E=Enough
F=Finished, Got it? :goodjob:
 

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Lug around a full tank? Better than the alternative. Besides, I have my wife keep hers full, mine gets filled up when it is nearer E than F, but that is because I am a guy and sketchy areas don't bother me as much. Besides, I don't drive half as much as the wife, and I have a spare tank (in the other car) if I am pressed for time and it is E.
 
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