Whats the most economic level to keep your fuel gauge at?

Beanstalk

Whats the most economic level to keep your petrol gauge at? Or does it matter?

I've been told that keeping it filled low means you carry less weight, and yet when I ahve it over half full it seems to go down slower.

Sorry if this is a silly question, it's just with the huge cost of petrol these days i'd love to save as mucha s I can.

p.s. I drive an 02 opel corsa.

Makes next to no difference really. How much in the tank won't effect the rate of use aside from the less weight which would be negligable enough really. If the petrol station visit is out of your way at all then brimming it is the best way. For fuel filter reasons etc going very low isn't advised.

mickdw

IN theory, the lighter the fuel amount, the less petrol you use however the difference in useage between tank levels in not worth talking about really. The reason the top half of the tank seems to last longer is that typically the fuel gauge is not linear. It does not truely represent exactly where half is etc. It is just fooling you. There is certainly no gain in keeping the car full all the time. There is also the possibility that when you fill the car completely that there is a certain amount of petrol in the filler neck above the full tank so the gauge wouldnt move at all til that was used.

shogunpower

well each liter is a kilogram, there is a 90 liter tank in mine, so a full tank is 90kg, half tank is 45, thats the weight of a light adult, 9stone, bound to save a little by keeping the weight down,

mickdw

shogunpower wrote: »

well each liter is a kilogram, there is a 90 liter tank in mine, so a full tank is 90kg, half tank is 45, thats the weight of a light adult, 9stone, bound to save a little by keeping the weight down,

Fill the tank with water do you?:D

helimachoptor

1litre != 1KG
1 litre of petrol weights 0.73722kg

shogunpower

shogunpower wrote: »

well each liter is a kilogram, there is a 90 liter tank in mine, so a full tank is 90kg, half tank is 45, thats the weight of a light adult, 9stone, bound to save a little by keeping the weight down,

9 stone is over 57kg, also a litre of water weights 1kg, petrol weighs less than water.

enda1

OP. Most efficient is to fill as rarely as possible and try fill in cold weather as the gauges are usually I think accurate at 15deg and so below this, the fuel will be more dense so for an equal volume you will have more molecules => more fuel.

Far, far, far, far more important than this though is to modify your driving habits and driving pattern. Stop using your car for short trips.
Stop braking into junctions. Stop hard accelerating. Don't drive too fast. etc. etc.

bazz26

When the fuel reserve warning light comes on I fill the tank to the brim. Only half filling the tank to keep the weight down in order to save fuel surely would be eliminated by the extra trips involved going to the filling station?

Esel

enda1 wrote: »

OP. Most efficient is to fill as rarely as possible and try fill in cold weather as the gauges are usually I think accurate at 15deg and so below this, the fuel will be more dense so for an equal volume you will have more molecules => more fuel..

Can't you get a black box on eBay to align those molecules on their way into the engine too? :pac:

brendansmith

bazz26 wrote: »

When the fuel reserve warning light comes on I fill the tank to the brim. Only half filling the tank to keep the weight down in order to save fuel surely would be eliminated by the extra trips involved going to the filling station?

Extra trips to the petrol station? I take it you live along way out in the country? I pass about 4 petrol stations on my way to work every day.

I keep my tank half full because it keeps the weight down and uses less petrol.
I do notice however that when I fill the car to the brim that the petrol gauge needle wont budge for the first good while but then makes a steady decline from there on. The reason for this I would imagine is that the guage in the tank is at its capacity about 10 litres before the car is full.

JerCotter7

shogunpower wrote: »

well each liter is a kilogram, there is a 90 liter tank in mine, so a full tank is 90kg, half tank is 45, thats the weight of a light adult, 9stone, bound to save a little by keeping the weight down,

Thought you had an e36? Which has a 60 liter tank. Not 90.

FunkDrummer

The key to saving cash here is avoiding a heavy foot on the accelerator. I drive from Dublin to Limerick every morning, and do the return journey every night, no matter how much fuel is in the tank, if I keep the revs low and watch my gears then my diesel lasts me a lot longer!

vdriver

It's not good to keep the fuel too low as some fuel pumps are cooled by the fuel itself.

shogunpower

JerCotter7 wrote: »

Thought you had an e36? Which has a 60 liter tank. Not 90.

yea i do, its not on the road at the moment, no idea what size the tank is, theres a 90 liter one on the jeep though.

my mistake i thought petrol weighed the same:o

Del2005

shogunpower wrote: »

yea i do, its not on the road at the moment, no idea what size the tank is, theres a 90 liter one on the jeep though.

Would a jeep not be safer with a heavy load in the back?

Also 80kg extra on 2+tonnes won't make much difference. if it was a Micra it might

Tea 1000

The difference in carrying around an extra 20kgs in a Corsa might mean an extra 3 miles out of 50 litres of petrol, in other words, I'd say negligable. You could get an extra 30 miles out of a tank by modifying your driving style.
Taking off from a complete stop uses more fuel too, so therefore stopping a second time for 50 litres of fuel might actually use the same as the savings of 20 kgs extra weight!

langdang

Tea 1000 wrote: »

Taking off from a complete stop uses more fuel too, so therefore stopping a second time for 50 litres of fuel might actually use the same as the savings of 20 kgs extra weight!

We could get loadsa lads on the dole to stand at traffic lights and petrol stations and push people away from standing starts. Hybrids me hole!

paddydriver

Beanstalk wrote: »

Whats the most economic level to keep your petrol gauge at? Or does it matter?

I've been told that keeping it filled low means you carry less weight, and yet when I ahve it over half full it seems to go down slower.

Sorry if this is a silly question, it's just with the huge cost of petrol these days i'd love to save as mucha s I can.

p.s. I drive an 02 opel corsa.

Put down the donut and lose a few pounds? You will feel better, your car will cost less to run and you will live longer:D

I just hate going to the petrol station. Everytime I go there I make sure not only is the tank full but also the filler neck is filled up the gills.

Bike is pain in the neck, have fill up every 350 km or so which gives me a range of about 8 work days. Car does between 650 and 800 km between the fills and van about 800. Happy days on those two although the van took over 80 liters last time I filled it and hence cost approx. 120 quid. Luckily it normally only needs to be filled once every two months or so.

None of my vehicles gets filled up until the low warning light has been on for some tens of kilometres maximising the time between the fills.

Esel

samih wrote: »

None of my vehicles gets filled up until the low warning light has been on for some tens of kilometres maximising the time between the fills.

Nothing a thief hates to see more than that warning light when he's driving away in/on your pride and joy....

I'm a €40 man myself (used to be €30...) - I find I get more litres per gallon that way.

Senna

Just to be an empty to filling to the neck driver, but moneys tighter now, so i put anywhere from €30-€50 in now depending on how far pay day is away:D.

101sean

Running a lot on empty does some in-tank pumps no good but I still do it now and then! Normally I brim fill when it's just above the orange bit on the gauge so I can keep an eye on the consumption (just did about 1500 miles on UK motorways in my Defender, keeping around 60ish made 3mpg difference, up to 27mpg from my usual 24mpg )

The fuel gauge issue varies from car to car but they are generally more accurate below half full (on my 3.5 V8 101 you can see it move if you floor it below 1/4 tank :eek:)

An old Clarkson saying is that real men know exactly how far they can drive with the needle wrapped round the stop and the warning light flashing!

Paparazzo

Before going on a long journey, make sure you have a dump and a slash to save weight. Get any coins you have and change them to notes too, this will also save weight. The weight reduction from hoovering the car alone can save you €10 on a 300km journey

Del2005

Esel wrote: »

Nothing a thief hates to see more than that warning light when he's driving away in/on your pride and joy....

They hate it so much they stick a lit match in the tank to check how much is actually left.

-Corkie-

shogunpower wrote: »

yea i do, its not on the road at the moment, no idea what size the tank is, theres a 90 liter one on the jeep though.

my mistake i thought petrol weighed the same:o

What happened it?????:)