Here are 12 tips for how to stretch a tank of gas.

1. Change your air filter. A clogged air filter leaves your engine gasping for breath and means you’re probably running with a “rich” mixture, that is, more gas and less air. Many department and auto stores carry air filters, and they are simple to change. A clogged air filter can cost you 1 mpg. Replace your air filter regularly.

2. Change your oil as recommmended by manufacturer. Usually every 3000 miles. Dirty oil cuts back engine efficiency, so make sure your oil is changed according to the car manufacturer’s recommended schedule. You can change your own, and buying your own oil is much cheaper. There’s a drain plug under your engine that will come out readily with a wrench. Have a bucket ready to catch the dirty oil, and remember to dispose of it safely and responsibly. NEVER empty your used oil in the sewer or in your lawn.

3. If your fan belt is too tight, your engine is working too hard and wasting gas. The belt should give a little to finger pressure when the engine is not running. if it doesn’t, you can easily adjust the tension with a wrench.

4. Change your old spark plugs. Badly worn spark plugs can cost you as much as 2 mpg. This is probably a job for a trained technician.

5. The car has been a way of life for most Americans. There are alternatives. These include mass transit, bike paths, and carpools.

6. Purchase smaller vehicles. Heavier cars are more costly to run. A reduction of 200 pounds in automotive weight typically improves fuel economy by nearly 5 percent.

7. Use the air conditioner in your car as little as possible. It uses a lot of gas. Roll down the windows and get some fresh air!

8. Using cruise control can save gas. If you drive on the open road often, staying at a constant speed will save fuel.

9. If you are taking a trip, start while traffic is light. Plan to stop for meals at times when traffic is heavy.

10. Don’t let your car idle for a long time to warm it up. Also, don’t let your car idle for more than a minute after it is warmed up-this idling wastes more gas than restarting your car.

11. Do not rev the engine and then quickly shut your car off. This wastes gas. It also pumps raw gasoline into the cylinder walls. This can wash away a film of oil that protects the cylinders and will increase engine wear.

12. Check your tires. Your owner’s manual has important information on your tires, including the correct air pressure that should be in them. Underinflation of your tires can cost you as much as 1 mpg. Radial tires have 50 percent less road resistance, so they give you 3 to 19 percent better mpg.