The final 'quarter' on the fuel gauge seems to be more of a third (or eighth?) or I seem to be using fuel at a higher rate when the tank's nearly full. I haven't really investigated the lower quarter, and would prefer not to.

There is a big difference between 1/3 and 1/8, and 1/4 sits somewhere in between.

I've never known fuel guages to be linear in any car I've had.

So did I. Octy is certainly not worse than others.

It seems to be the case on most cars. Once the fuel gauge has got past ½ it drops faster. So ½ isn't really ½

I get a warning when 60 (?) miles is left so plenty of time to worry about refuelling.

I usually refuel at about 1/4 full when I need to buy a sandwich or a lottery ticket.

The gauge is as accurate as any I've had- tanks are not of a uniform cross section all the way down.

The gauge is as accurate as any I've had- tanks are not of a uniform cross section all the way down.

This is true but they could probably compensate for this with a programmable device if they wanted to. However it's not really worth it because as you say there is ample indication of when the remaining fuel's getting low. The fuel gauge on my 1.4 TSI takes some time to move from it's full reading but does start to drop more rapidly once around the 1/4 full mark. This is similar to other cars I've owned.

some how doubt the tank is a nice regular shape, therefore the instrumentation will have to have some form of compensation thats far from perfect

Fuel gauges always take ages to start moving from full as the fuel level is usually a fair bit higher than the top of the level sensor so it needs to drop past it before you see any movement on the gauge.

Software correction used to prevent the gauge going nuts round every corner can also compensate for the 'odd' shape of most fuel tanks, because of this it will never be 100% linear.

A similar thing is applied to temperature gauges, minor fluctuations are ignored and the gauge will sit at 90 degrees unless there is a real problem.

It seems to be the case on most cars. Once the fuel gauge has got past ½ it drops faster. So ½ isn't really ½

I was thinking 1/2 probably was 1/2 but 3/4 was more like 5/6 and 1/4 was more like 1/6. I might find a non-busy filling station with a level forecourt and put a few squirts of 5litres and see what the gauge shows after each squirt.

I've never known fuel guages to be linear in any car I've had.

The gauge in my previous car seemed to be more linear over the fourth quarter than this.

My gauge certainly drops very fast once I hit the red section at the bottom... Still didn't stop me covering 110 miles on less than a quarter tank last weekend though...

There was mention of some one of the maxidot mods out there that adds the option of displaying how much fuel remains in the tank in litres - if I had maxidot I'd be very interested in that one...

There was mention of some one of the maxidot mods out there that adds the option of displaying how much fuel remains in the tank in litres - if I had maxidot I'd be very interested in that one...

I've got Maxidot but I can't remember whether this is an option or not. However as far as I can see knowing how much fuel in litres is left is only useful to work out how many miles you've got left before needing to re-fuel and the Maxidot does that for you.

It's not a standard option, but turns up when a separate module is added (I saw it in a post on this forum ages ago). I'd rather see an actual figure for what fuel is left as the 5 mile resolution on the car's range isn't really worth a whole lot if you're nearly empty... I know the car will do heading for 10miles with a range of 0 miles on the computer though (Found this out without actually running out of fuel too thankfully).

the fuel warning comes on showing 100kms to go, but when it reads 0kms to go I can still drive another 50kms before filling up.

So I was getting stressed for nothing by the time I got to the filling station after 10 miles of no range? Did you run it empty to find that range? My car took slightly over 55 litres IIRC after all the time on empty, so it makes you wonder what the real fuel capacity of the car is.

Weight Of the Pin I'd Say

ok ok i'm going :P

Fuel gauges always take ages to start moving from full as the fuel level is usually a fair bit higher than the top of the level sensor so it needs to drop past it before you see any movement on the gauge.

Software correction used to prevent the gauge going nuts round every corner can also compensate for the 'odd' shape of most fuel tanks, because of this it will never be 100% linear.

A similar thing is applied to temperature gauges, minor fluctuations are ignored and the gauge will sit at 90 degrees unless there is a real problem.

theres linearisation in the instrumentation and a lot of damping. If you've ever filled up with the ignition on and watched how long it takes the needle to start going backwards you'll see just how heavily damped the system is

I believe the manual warns against running out of petrol completely, I think it may because misfiring whilst it's pumping new fuel through can damage the catalytic convertor.

The damping used to be done by using a hot wire meter. The wire took a while to warm up and cool down so didn't show the fuel sloshing about and it lagged a bit while filling for the same reason.

I remember my dad's friend had an NSU and that had a standard moving coil meter instead of a hot wire one and the gauge was all over the place. When you stopped, the gauge would wobble for a while.

I suppose they do it today with software.

D

So I was getting stressed for nothing by the time I got to the filling station after 10 miles of no range? Did you run it empty to find that range? My car took slightly over 55 litres IIRC after all the time on empty, so it makes you wonder what the real fuel capacity of the car is.

I sometimes play the stupid " how far will it go" game !! I wouldn't be too worried about going 10miles past zero range. Mine is a Diesel so it will be a little different for petrol models I would think. The tank is 55 litres so it will take a few more if you brim it from empty.

along with the tank you have the pipe going into the tank and this is why the first quarter seems to take a while to the rest of the tank.

The game you refer to is called 'Fuel light bingo'

My personal best is about 25 miles on 0.

The game you refer to is called 'Fuel light bingo'

My personal best is about 25 miles on 0.

Best played with a dead gauge IME :eek: