Is it just me??? Fuel

[tim_sugar]

So today noticed my mk5 R32 was at beginning of the red lines for low fuel. Checked the dash to see how much was left and it said 80kms. So i stopped got myself a boost drink then jumped back in. As i drove past the servo(no more than 200m) the line was on empty and the dash was reading as nothing. How can it go from 80kms left to none?? Is this just me?

Cheers

[Stan]

probably reliability of the gauge at it's extreme points of operation - like when mine reads full it takes about 150kms to budge off the mark

[NabzGTI]

I notice the same thing on a steep hill. It can drop about 1/16 of the entire fuel gauge. so that's half of half a quarter lol (somtimes a little more)

[Idle]

Quite likely just fuel flowing away from the guage pickup with changing road angle.

[jettapilot]

I believe the distance to empty calculation is based fuel economy of recent driving history. I've been driving with 80kms left then it goes up to 100 and back to 60 as conditions change. Best to refill at 1/4 tank - just in case.

I hate stopping to refuel. That's as good a reason as I can think of to drive diesel.

[VW Central]

I think its more to do with, when you start the car, it uses more fuel initially and once you keep driving it will increase as your fuel economy drops.

[Treza360]

When the fuel is that low anyway the computer is at it's most inaccurate. In my new wheels once the fuel light comes on in the red the distance to empty goes to "---" to show that it can't accurately show this.

As jettapilot said it will depend on how you drive but in my R it was roughly 50-80km before the needle was basically below empty and I would put pretty much a full tank into the car. I think I actually put am extra half a liter more once than the capacity of the tank.

Cheers,
Trent

[j_man]

probably reliability of the gauge at it's extreme points of operation - like when mine reads full it takes about 150kms to budge off the mark

AHHHHH good I thought mine was playing up I filled it full and its been stuck on needle @ full (630-640KM remaining) for 50kms so far!

[blutopless2]

I'm really surprised the number of times I've read on here about how people drive their cars almost empty before filling up.
It's a gauge.... as the name implies it "roughly" indicates what is going on. They shouldn't be trusted as the exact reading.
When you fill the car it doesn't stop at the full mark - unless that's where the needle stop is... so you can only hope its calibrated to be more accurate at the empty end... but i doubt it.

[Gigitt]

how can the fuel gauge sender inside the tank which is under the rear seat area measure all the fuel above it in the filler nozzel... it can't! hence why you read FULL for 100km till those 5-7 extra litres of fuel are used up and the level of fuel can now start to be measured as the sender is bobbing up and down. Similarly on empty... does the sender sit on the bottom of the tank... probably not for all cars, but topless2 said fuel gauge is just a instrument that "gauges" how much fuel is in the tank. You get to know how far YOUR car can go and how much juice is left in the tank when the needle is on E... but best not to temp fate as you will be walking to a servo sooner than later if you believe the distance to empty.

On my last trip to the farm I drove it from Sydney to the farm then back to Scone Wollies/Caltex on a tank... just to see... 975km with 45 km reading on the Distance to empty - was just above the E

[MariusGT]

going up hill (stuck in traffic) my gauge will read less than is in there - vice versa for downhill.

as for end and beginning of the tank - Full is full for approx 50-80kms before it starts dropping as others have mentioned.
i have driven to 0 (indicated on MFD) several times in remote locations and when filled have only managed to cram 50 liters in even though it is a 55 liter tank. suggesting there was 5 or so left (plus whatever is in the lines) and a good 50-80kms to go.

evidence suggests it errs on the side of caution for being empty. which is a good thing! and if you still manage to run out... then that's either unlucky due to location circumstance or just a bit silly.

[99_FGT]

Pretty sure that unless you are - as marius said- sitting in traffic on a hill that the guage uses a PI loop or some sort of RC filter so the gauge will not react to the sender bobbing up and down etc. So when you start your car, the sender reacts and gradually adjusts to what it is reading, but when you stopped and restarted the trip it starts that process again. Seen mine do it with the DTE before.

[jessv3]

I've found the gauge in my gti fairly accurate but like most cars the last quarter seems to drop quite rapidly, I usually rely on my odometer which I reset every fill up, once I hit around 420kms I known its time to start looking for a caltex.