Ebay "Fuel Savers"?

[thelusiv]

Here's my short list of how to improve your gas mileage. Ranked from biggest difference to smallest. Use at your own risk. Your mileage may vary (literally).
* Drive a manual.
* Drive like grandma - accelerate slowly and don't go over the speed limit. Also, avoid idling, coast to stop lights instead of accelerating to them and stopping right before you get there. Try to stay as much as possible in low RPMs, in high gears. 5th gear is your gas saver gear. Use it from 45 MPH up.
* Coast. If you know that the next half-mile or more will be downhill, get up to speed, put it in neutral and turn your engine off. (Note that your power brakes and power steering will not work, don't do this in heavy traffic!) When you start back up, don't use the starter, put it in 4th or 5th gear and let the clutch out. When coasting with the engine on, leave the car in gear, most cars will cut the fuel, while in neutral it goes back to idle, which does not cut the fuel.
* Inflate your tires to 50-60 psi. Your tires will not blow up. The manufacturers recommend 35 psi for a softer ride but higher pressure is actually safer and will reduce rolling resistance. Check your tire pressure regularly, and rotate your tires regularly.
* Make sure you have a good alignment. Get an alignment at least every time you get a new set of tires, possibly more often if you drive on a lot of bumpy roads or drive hard.
* Make sure you have a good air filter. A clogged one will impede a little. A high-flow filter will give you a very slight, probably unnoticeable change.
* Make sure your O2 sensor is working. The ECU responds to a bad O2 sensor by dumping more fuel.
* Use a lighter synthetic oil. Often if your car requires 10w30 you can get probably away with syn 5w30 or even 0w30 (the latter is expensive though). Don't bother if your car burns oil. Don't do this until you read up on oil and get an oil pressure gauge.
* Obvious aero improvements. Remove roof racks you don't use. Get an interior antenna for your radio and remove the exterior one. If you race your car, keep your spoiler, otherwise, delete it (if anything get one of those neat little "lips" that just barely sticks up off the edge of your trunk because they look so awesome).