Fuel gauge poser

[poohbah]

Bit of a conundrum.

Why is it that the first quarter of a tank of fuel - as indicated by the gauge - seems to last for a lot more km than each subsequent quarter tank as shown on the gauge? Its been a common trait of all 3 Alfas I've had (its been so long since I've driven another make regularly enough to know if they do it too).

For example, my current 156 V6 will regularly cover 180 - 220km before the gauge hits the quarter mark, but unless I only travel on country roads thereafter, I don't get close to 800km from a whole tank. Typically, I will get 600-650km from a tank. My first V6 was similar.

My 116 GTV will generally do 130-150km before I hit the quarter mark, but I will generally get no more than 400km from the whole tank (though I don't usually risk testing it that hard as I don't want to stir up the crud in the bottom of the 35yo tank)

Why is it so?

[poohbah]

Well I've done some extensive Google research and have found an answer. It's apparently deliberate!

http://www.autoblog.com/2010/12/14/gas-gauge/

At least now I know I'm not imagining it.

[colcol]

My 156 JTS is the same, do 100 klms before it moves off full.
33 is different, do 50 klms and the tank gauge moves to 7/8 full.
Some fuel gauges have the hose of the petrol bowser showing where the filler is on the car, such as showing the hose on the right side of the bowser, means that the filler cap is on the left side of the car, and vice versa for a right hand side filler.
Still doesn't stop this particulary thick Alfa Romeo driver from pulling up on the wrong side of the bowser, cause he thinks he is in the other car, and then stretches the hose around to the other, [wrong] side of the car, and acts as if everything is normal, Colin.

[poohbah]

Until you mentioned it I hadn't even consciously thought about the location of the filler cap. How odd - it's on the left side of the GTV but on the right side of the 156. I can only assume it has to do with Alfa getting around to changing the configuration for LHD and RHD markets for later models.

[colcol]

Checked the 33 fuel gauge, hose is on right side of fuel bowser on fuel gauge, so it is correct, so it corresponds with filler cap being on left side of car.
On 156, it has the same fuel bowser symbol on the fuel gauge, with the hose on the right side of the bowser, the fuel filler is on the right side of the car, so either the fuel gauge hose is on the wrong side of the gauge OR the fuel filler is on the wrong side of the car.
This is why i always pull up on the wrong side at the service station.
Need to change the filler to the left side of the car OR pull the fuel gauge out of the dashboard and black out the hose and draw a new one on the left side of the bowser.
Looked at a VT Commodore and it also has the same mistake as the 156.
Need to go back to HQ Holdens, where the fuel cap was behind the number plate, in the centre of the bumper bar, so it doesn't matter what side of the fuel bowser you pull up next to.
That is more than enough nonsense from me, Colin.