less weight (ex: keep you car clean) proper air in tires (should be 30 psi, check driver side door sticker for air pressure) regular maintenance buy laser platinum spark plugs ($8 a piece, need 4) aerodynamics (ex: body kit) using less A/C (having A/C on take up 30% horse power there fore having A/C on requires more power, more power means more fuel) using higher octane (thats debatable)
No!
in the gas tank
Helps improve fuel mileage.
You can try a fuel catalyst. If you google, "how to improve gas mileage" you'll find a bunch of suggestions. I'm trying a product called Fuel Infusion (http://www.fuelinfusion.com) right now and seeing between 10-15% better mileage. There's lots of things to try, but this might be a good product to test.
yes, but they require that you only run Premium fuel. The savings on mileage is offset by the extra cost of the fuel, and its not worth it.
20 to 30 miles
If you are referring to E85, from my experience using E85 actually lowers the fuel economy.
Every 46,000 Miles or 46 Months
Install a hydrogen fuel cell. Google fuel cell llc. I noticed their first cell produce is for the N14
Keeping up with scheduled maintenance, better driving habits... a lot's been done since ACERT went into effect in the early 2000s which has impaired fuel mileage... EGRs decreased fuel mileage, SCR/DPF/DEF decreases fuel mileage, 2007 introduced Ultra Low Sulphur Diesel - which is a less efficient fuel than the previous low sulphur diese - all in the name of emissions. Turbocharging remains the best option to improve diesel efficiency.
Any number of things can improve gas mileage on any car, such as; -full tuneup i.e. plugs, wires, cap/rotor if applicable, PCV valve, fuel filter, air filter -Fuel system cleaner, intake cleaning like EGR ports -making sure brakes are free, no binding -driving habits -tire pressure
no, they just mean that the engine has a supply of hydrogen to run on rather than any other fuel