Anyone have any tips for saving money on fuel for your car?

[Lisa23]

Here's what I have so far:
1. Only fill up your car in the early morning when the ground temperature is still cold. The colder the ground the more dense the gasoline. When it gets warmer gasoline expands so when buying in the afternoon or evening… your gallon is not exactly a gallon.
2. 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. In slow mode you should be pumping on low speed, thereby minimizing the vapors that are created while you are pumping. All hoses at the pump have a vapor return. If you are pumping on the fast rate, some of the liquid that goes to your tank becomes vapor. Those vapors are being sucked up and back into the underground storage tank so you’re getting less for your money.
3. Fill up when your gas tank is HALF FULL or HALF EMPTY. The more gas you have in your tank, the less air occupying its empty space. Gasoline evaporates faster than you can imagine.
4. If there is a gasoline truck pumping into the storage tanks when you stop to buy gas, DO NOT fill up. Most likely the gasoline is being stirred up as the gas is being delivered, and you might pick up some of the dirt that normally settles on the bottom.
and a few of my own:
5. Use cruise control whenever you can. The steady electronic acceleration uses less gas than pressing the pedal manually.
6. Don’t let your car idle needlessly for long periods of time. Your burning gas but not going any where.
Greener Pastures

[hermione]

1. Lighten the load as much as possible
   Clear out anything from the trunk or backseat that adds additional weight.
2. Keep to the speed limit
   From CNN Money: "In a typical family sedan, every 10 miles per hour you drive over 60 is like the price of gasoline going up about54 cents a gallon. That figure will be even higher for less fuel-efficient vehicles that go fewer miles on a gallon to start with." Also, this will decrease the risk of getting a speeding ticket.
3. Consolidate outings
   Try to arrange your schedule so that you can run multiple errands in one trip. Plan out the most efficient route time- and gas-wise. Take into account lights, turns, and one-way streets.
4. Shop online
   Shipping and handling costs are often less than the overall gas and wear-and-tear of driving. Also, online prices are often lower than in store. Save time, money and the planet.

[amyschiff]

I agree that driving fast is very inefficient fuel-wise. What makes it tough is in MI some of the speed limits are 70mph on the highway, so it's hard to drive much below 65 in the right lane.

[gt0163c]

A couple of comments:

Originally Posted by Lisa23

1. Only fill up your car in the early morning when the ground temperature is still cold. The colder the ground the more dense the gasoline. When it gets warmer gasoline expands so when buying in the afternoon or evening… your gallon is not exactly a gallon.
2. 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. In slow mode you should be pumping on low speed, thereby minimizing the vapors that are created while you are pumping. All hoses at the pump have a vapor return. If you are pumping on the fast rate, some of the liquid that goes to your tank becomes vapor. Those vapors are being sucked up and back into the underground storage tank so you’re getting less for your money.
3. Fill up when your gas tank is HALF FULL or HALF EMPTY. The more gas you have in your tank, the less air occupying its empty space. Gasoline evaporates faster than you can imagine.

These two seem to contradict each other. If gasoline really does evaporate that quickly, then you'd want to get the gasoline into your tank as quickly as possible, thereby limiting the amount of time that the gasoline has to evaporate.
Now, there will be a slight heating of the gasoline as it moves through the gasoline pump tubing and into your vehicle (cause by the friction of the fuel against the inside of the hoses). And that friction will increase with the speed and pressure of the fuel. So, I'm sure that there's a break even point in terms of heat generated (and therefore increase in the evaporation rate) vs time the gasoline is exposed to air and has to evaporate, but I'm not certain where it is. I would guess that the increased evaporation due to heating caused by friction would be minimal. So, unless someone has done or can do the math, I'm not certain I agree that pumping gas on the slowest setting that the pump will allow will generate a cost savings.

Additionally, unless there is a leak in your fuel system, your gas tank to fuel injectors should be a closed system. Therefore, no gas should evaporate out of your tank regardless of the gas level in your tank. It is true that with less gas in your tank, there will be a greater percentage of your tank that is filled with gasoline vapor rather than liquid gasoline, but that will not effect your fuel economy, the gas is still in there and will still be used. And, in fact, opening your fuel system twice as often (which you do when you take the gas cap off to put more fuel in) may cause extra evaporation as some gasoline vapor will escape.

Originally Posted by Lisa23

4. If there is a gasoline truck pumping into the storage tanks when you stop to buy gas, DO NOT fill up. Most likely the gasoline is being stirred up as the gas is being delivered, and you might pick up some of the dirt that normally settles on the bottom.

Also, the water that accumulates in the gasoline tanks may be more mixed up with the gas as well. In general, it's better to wait a bit after the fuel tank has finished delivering gas. However, it's not always possible to know that. And, the fuel filter in your car will generally deal with any of the contaminants which get into your gas. Frequent refueling right after/while the tanker truck has/is delivering gas may result in a need to change your fuel filter more frequently, but as long as that is done, it shouldn't result in any issues with your vehicle.

[lucille]

We try to not fill up and gas stations that are old and starting to lack maintenance or that don't have a steady stream of business.

Older stations are more likely to have leaking tanks that could have water in them. We have been burned by this twice. Stopping at old run down stations because we were getting low and they were right there. Both resulted in long drawn out attempts to undo the damage and either draining or running the tank empty.

It might not save you gas but it will save you money not to end up in that situation.

[Lisa23]

I had water in my tank once from bad fuel- what a pain! At least I think it was water. the car ran really rough, just for that tank of gas. When I filled it again, things got better.

[72Tiger]

some tips here. some more practical than others:

http://www.wikihow.com/Save-Money-on-Gas

One that was interesting is to run your tank to close to empty because you are carrying around less weight in fuel that way.

[robothuman]

You can also drive with the windows open during city driving. Cars burn gas more quickly at slower speeds and spending less energy on AC can decrease fuel consumption slightly. But then you have to balance it against the idea that you'll have the windows open, sucking in all those fumes during a traffic jam...

[saint tim]

Mythbusters proved that you got 15 more miles to a tank of gas if you drive with no A/C. Even on the highway (they were busting the myth that wind resistance from open windows decreased the mpg)

[kav122]

Originally Posted by Lisa23

Here's what I have so far:
2. 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. In slow mode you should be pumping on low speed, thereby minimizing the vapors that are created while you are pumping. All hoses at the pump have a vapor return. If you are pumping on the fast rate, some of the liquid that goes to your tank becomes vapor. Those vapors are being sucked up and back into the underground storage tank so you’re getting less for your money.
3. Fill up when your gas tank is HALF FULL or HALF EMPTY. The more gas you have in your tank, the less air occupying its empty space. Gasoline evaporates faster than you can imagine.

Greener Pastures

Ok, I totally don't get these. First of all, have you ever tried to pump gas on the low setting?????? I did it accidentally one time, got in the car and was pre-occupied with something for what seemed like FOREVER. I was wondering why the pump hadn't popped yet, so I look out and there was $1.00's worth of gas in there!!!! ONE DOLLAR. That took at least a couple of minutes and multiply that by 40=I am not sitting at a gas pump for over an hour to pump gas.

point number two: If gas evaporates THAT quickly then why doesn't it evaporate in your snowplow when you don't use it for a couple of weeks. Or your lawnmower.

Sorry, charlie~I usually love your lists, but I am not buying this one.