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Discussion Starter #1
I've come to realize that my MGP drops after the half tank mark :confused: I'll be getting about 22 mpg before it. Between the half tank mark and the quarter mark i get abot 17-18 mpg and between the quarter mark and barely below the beginning of the red i got like 15-16 0_o


ok, I've changed the air filter . Change the oil and oil filter, cleaned the MAF, had te timing belt and waterpump changed, checked the fuses, ran a bottle of fuel system cleaner, and can't get the codes scanned at autozone because they no longer do that in CA, and I also don't have much money to take her in and be checked out since I just had to pay for a new coolant flange

does anyone else have this problem? I haven't tried disconnecting the battery yet because I'm afraid I'll mess somehing up
 

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No NB Yellow Trifecta :(
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I have read many posts regarding lower than expected mileage, if you perform a search you should find a few. See if there is someone in CA that has VCDS (Vag-Com) to scan your NB.
 

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Discussion Starter #4
How are you calculating to get your MPG?
by the half tank mark I'll have about 168 miles, tank has 14.5 gallons divide that by 2 says that half a tank is 7.25 gallons. 168/7.25= about 23 mpg. Cool. At the half mark I reset the miles and get like 66 miles by the time it's at the quarter mark, quarter tank is 3.625, 66/3.625= 18 mpg. Whhhhaaaatttt? :confused:

It also seems like my fuel gauge wavers, sometimes it will say I'm right on one of the tick marks, but while I'm driving it'll move up in-between the mark it was on and he mark before it and then it'll go back to the mark it was on in the first place after driving a bit more
 

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5/23/10 <3
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The fuel gauge isn't the most accurate. Figure out your MPGs by total miles traveled on a tank/gallons put in the car when filled up. The gauges do tend to go down quicker in the 2nd half...at least mine has for years. Still pulling 23-25mpg around town even though it seems like junk mileage.

It also seems like my fuel gauge wavers, sometimes it will say I'm right on one of the tick marks, but while I'm driving it'll move up in-between the mark it was on and he mark before it and then it'll go back to the mark it was on in the first place after driving a bit more
Mine has been doing this for probably the last 6 months to a year. It seems almost like the dampening of the gauge isn't so great anymore. I'll have 60 miles on the tank and be a tick or so above full. Look down a minute later and I'm at the 1/4 tank mark. Another minute later its down closer to where it was originally. Its really annoying...
 

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by the half tank mark I'll have about 168 miles, tank has 14.5 gallons divide that by 2 says that half a tank is 7.25 gallons. 168/7.25= about 23 mpg. Cool. At the half mark I reset the miles and get like 66 miles by the time it's at the quarter mark, quarter tank is 3.625, 66/3.625= 18 mpg. Whhhhaaaatttt? :confused:
A fuel gauge on any vehicle is not a linear device. Gas tanks are not perfectly shaped as a rectangle and so there is no car made that the fuel gauge accurately shows an exact amount, just overall. It's also why the gauge will show full for the first 50 or so miles after a tank is completely full and then starts to drop. On most cars you can almost watch the gauge drop the last 1/4 of a tank. Like was stated, record your mileage, fill the tank and drive. Note the current mileage, refill the tank, and divide the miles driven by the gallons it took to fill it.
 

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Mine has been doing this for probably the last 6 months to a year. It seems almost like the dampening of the gauge isn't so great anymore. I'll have 60 miles on the tank and be a tick or so above full. Look down a minute later and I'm at the 1/4 tank mark. Another minute later its down closer to where it was originally. Its really annoying...
Some good reading.

VW Beetle (new shape) dashboard instrument cluster problems
 

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Discussion Starter #8
thankyou everyone for your replies, I've been doing reading on both poor MPGs and fuel gauges on the forum, and there was one fairly old post about how the gauge isn't really accurate

I feel a bit more relieved to know that Im not the first to experience the weird fuel gauge thing. I'll keep recording my mileage whenever I fill up. it never occurred to me that I should calculate my mpg by dividing the miles by the amount of gas I fill up with
 

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A fuel gauge on any vehicle is not a linear device. Gas tanks are not perfectly shaped as a rectangle and so there is no car made that the fuel gauge accurately shows an exact amount, just overall. It's also why the gauge will show full for the first 50 or so miles after a tank is completely full and then starts to drop. On most cars you can almost watch the gauge drop the last 1/4 of a tank. Like was stated, record your mileage, fill the tank and drive. Note the current mileage, refill the tank, and divide the miles driven by the gallons it took to fill it.
Unless it's a diesel. 50mpg isn't unheard of for them. I don't tick off full till well past 120 miles....230ish at the first quarter, 360 to the half, 580-630 (a range, I know, depends on hwy or city driving) at the warning beep. Twice I've had the warning beet at 703 miles... that was strict highway driving tho. Just saying, for gas cars... what you say is correct, but for those with a diesel the gauge shouldn't move after 50 miles.
 

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you say insane, i say it should be today's minimum baseline.

i see these new cars toting a 600 mile range -- and an 18 to 20 gallon tank. my car is built around a motor audi introduced in 1989. it's nothing new, it's nothing special, it's long lasting and very economical and frankly on a pollution per mile standpoint (read: european not american) it's cleaner than gas engines.

these electrics with a sub-300 mile range, i'd kill myself. I fill up two to three times a month on average, without out of town travel. 600-650 is "average" range for the tank (13-14 gallons), I put about 14.7 in on those long range trips (731 miles is the trip distance). I've never pushed it more than that, my Jetta I got 775 out of and ran it bone dry -- 15.3 gallons to fill it totally back up.
 

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these electrics with a sub-300 mile range, i'd kill myself.
I'll tell you what's REALLY sad, back in 1990 you could buy a GM full size car Olds 88 or Buick LeSabre with a 3800 V6 with 170 hp, very good size interior and trunk, and they would do 33 mpg all day long. With all the developments and controls we have and they now brag if a shoe box size car with a 1.8l 4 cylinder gets 30+ mpg?????? Seems like they are going the wrong way to me. I'm starting to see why there is such a following for a TDI.
 

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90s cars (shy SUVs) did seem to get 30-35 all the time, then safety requirements and bigger AC systems seems to have chewed that down. My friend tranded an 89 Golf for a Yaris, the Yaris has even less power and actually gets the same or worse fuel economy, with a smaller sized engine. I also think automatics have a lot to blame for reduced fuel economy, we are the only country in the world with more gas to diesel engines and more automatics to manuals, and we consume most of the world's energy supply yet make up about 1/3 the total population...

it's a little sickening.
 

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The thing is, the new automatics are 5, 6, and 7 speed boxes with a locking torque converter, they should do REALLY well as far as fuel goes. You can take a 400 HP current Corvette and both 5th and 6th are overdriven. The thing will actually get nearly 30 mpg on the highway (while turning about 1400 rpm). I just don't get why these new small aerodynamic cars get such crap mileage. My company car is a 2010 Pontiac G6 with a 2.4L engine. Makes 164 hp and it gets nearly 40 mpg on the highway in the warm weather. Good thing they don't make Pontiacs any more.:rolleyes:
 
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