Only buy or fill up your car or truck in the early morning when the ground temperature is still cold. Remember that all service stations have their storage tanks buried below ground. The colder the ground the more dense the petrol, when it gets warmer petrol expands, so buying in the afternoon or in the evening....your litre is not exactly a litre. In the petroleum business, the specific gravity and the temperature of the petrol, diesel and jet fuel, ethanol and other petroleum products plays an important role. A 1-degree rise in temperature is a big deal for this business. But the service stations do not have temperature compensation at the pumps.

When you're filling up do not squeeze the trigger of the nozzle to a fast mode If you look you will see that the trigger has three (3) stages: low, middle, and high. You should be pumping on low mode, thereby minimizing the vapours that are created while you are pumping. All hoses at the pump have a vapour return. If you are pumping on the fast rate, some of the liquid that goes to your tank becomes vapour. Those vapours are being sucked up and back into the underground storage tank so you're getting less worth for your money.

One of the most important tips is to fill up when your Petrol tank is HALF FULL. The reason for this is the more Petrol you have in your tank the less air occupying its empty space. petrol evaporates faster than you can imagine. petrol storage tanks have an internal floating roof. This roof serves as zero clearance between the Petrol and the atmosphere, so it minimizes the evaporation.

Another reminder, if there is a petrol truck pumping into the storage tanks when you stop to buy Petrol, DO NOT fill up; most likely the petrol is being stirred up as the Petrol is being delivered, and you might pick up some of the dirt that normally settles on the bottom.

And for those who only use the side that their petrol cap is on:

Thats exactly the right thing to do

sssshhhhh

Dodgy tips pa.

Always run your car nearly EMPTY if you really want to save pennies. Extra weight = extra work = extra fuel = extra money.

That's what me old da used to tell me....Only half fill it up (not sure how much difference it makes)

Another tip.

If you're in a strange car, and you don't know what side your cap is on. Have a look at the little petrol pump motif on your petrol gauge.



It'll indicate what side your cap is.

I thought this had been debunked?

If you ever find yourself in Bury St Edmunds, find Asda and fill up there. Cheapest price in East Anglia.

Exactly.

The other solution on petrol consumption is to say that you don't give a shit and just want to get your destination quicker.

I apologise for one of the most boring posts I've ever made. zzzzzzzzzzz !!

This was taken from a website based on PA's original text:

Analysis: In researching the contents of this much-discussed email I found disagreement among presumed experts as to the accuracy of the specific claims, but a general consensus of opinion that whatever modest savings might result from following these measures, they're probably more trouble than they're worth for the individual consumer. Let's take them one by one:

1. Fill your tank in the morning when the temperature is cooler so you get more volume for your money?

The basic science behind this is correct. Liquids expand as they warm. The figure usually cited for gasoline is about a 1% increase in volume per 15-degree rise in temperature. Therefore, if you buy 20 gallons of gas at a 90-degree temperature, due to expansion you end up with about 2% less product for your money than you would have gotten had you pumped 60-degree gasoline. At a retail price of $3.00 per gallon that differential would cost you $1.20.

The thing is, given that the gasoline is pumped from huge underground tanks wherein the temperature is less variable than that of the outside air, it's very unlikely you would encounter a 30-degree variance in fuel temperature in a 24-hour period. In fact, says a physicist interviewed by KLTV News in Jacksonville, over the course of a day the fuel temperature probably varies no more than a scant few degrees, so the actual savings from pumping in the morning would likely amount to only a few cents per fill-up.

2. Don't pump gas if a tanker truck is filling the station's holding tanks, because you'll end up putting dislodged sediment into your own tank?

Probably not. Modern gasoline holding tanks and pumping systems contain filters designed to block any such debris from reaching your car's gas tank. Should some particles squeak by, your engine's fuel filter ought to have no problem taking care of them.

3. Pump gas when your tank is no more than half-empty, because the emptier the tank the more you will lose to evaporation?

The idea here seems to be that the more unfilled space there is in the tank the more gasoline will be able to evaporate and escape into the atmosphere when you open the cap. Which makes sense, although according to physicist Ted Forringer the actual amount of vapor lost this way would be miniscule, adding up to only a few cents' worth per fill-up. A more important concern is the quality and fit of your gas cap, the job of which, in part, is to minimize evaporation on an ongoing basis. By one estimate, a poorly sealed gas cap can result in the evaporation of a gallon of gas in just two weeks' time.

4. Pump gas at the low-speed rather than the high-speed setting because the latter causes more agitation, thus more evaporation?

It does seem logical to assume that the higher the speed of the pump the more it may agitate the fuel, causing more evaporation. But consider this: the longer it takes to pump the fuel the more evaporation can occur too, so any benefits to pumping at the slower speed are probably negated.

Tips that really work

If all this just leaves you feeling frustrated and confused, don't despair. Edmunds.com has actually tested some of the most common gas-saving tips and shares the ones that really work http://www.edmunds.com/fuel-economy/we-test-the-tips.htmland http://www.edmunds.com/fuel-economy/we-test-the-tips-part-ii.html.

If you're a woman in the car in front of me tonight whilst I'm queuing up to get petrol then take ages in the shop buying sweets for your kids, come back, get in the car, put your seatbelt on, turn the radio down, eff about opening the sweets for the kids, eff about with your mirror and, whatever you do, don't worry about the rest of us waiting to get on wih our lives.

Or you could Spend £60 at Sainsburys and get 10p off per litre.

+1...and I wasn't even there.

FISO comradery at it's finest!

+2...and I was in the car in front calming down those pesky kids who thought they could have a go at me for cross dressing

Digsby - Murf does not have kids so I suggest you contact the police about a possible abduction through sweet bribery

The lady in front of me at the Filling Station on Sunday put her credit card into the machine and then realised that she didn't know her Pin Nr, but hold on, she had written it in her diary which was in the glove compartment of her car.

At least she was paying at the pump. One of my pet hates is people ignoring that facility then traipsing off to queue in the shop just to pay for their petrol by credit card.

Oh yes, how frustrating is that! I don't what people think will happen but it certainly shows just how much some people hate change.

Btw, thanks for the info stuboy. Saved me doing it.

EXCUSE ME !! How many times have I been stuck at the pumps because men need two car spaces in order to fill up their cars and then spend 15mts in the shop arguing about the best lager to take home with them. Another 5mts is then spent scratching their balls and picking their noses before putting the key in the ignition and moving off.

I always pay at pump if I can. Why can't the pump scan the 5p/10p off a litre coupons that their adjacent supermarkets give out from time to time?

I always go to my local garage to fill up but its so busy I always go at night - only trouble is its so dark I have trouble getting the nozzle in the tank - luckily I keep a lighter in the car.

With a bit of effort and training you could save a fortune. The downside obviously is the cost of the Dogs, vets bills, feeding them etc - ahh another theory debunked

A female on FISO!!!!!!!!!!!!!!!!!!!!!!

What is the world coming to

Beer, balls and bogies. She's got us sussed already

You forgot the sniffing part before noses get picked.

My pet theory is if everybody just topped up to the 1/2 or 3/4 mark, fuel would be stored by the petrol companies unpaid, rather than in our tanks paid. Would they then be forced to cut prices due to supply and demand?