AttemptGreen.com

Maintaining your car is very important for keeping your car running, extending the life of your car, as well as for safety.  But as Eric pointed out, it is also important for your full economy and emissions.  I’ve looked at a variety of sources online that all provide varying information on things that effect fuel economy, but three things are consistently listed.

1. Tire pressure – many sources say that if your tires aren’t properly inflated, it can cause a 2-3% loss in fuel efficiency.  At $3/gallon of gas, that is essentially losing $0.09 for every gallon of gas you buy while your tires aren’t properly inflated.
2. Air filter – sources site that not having a clean air filter can cause up to a 30% loss in fuel efficiency!  I was most surprised at this, but thinking about it, it makes sense.  If then engine doesn’t have proper air flow getting to it, how could it run efficiently.
3. Lighten the load – the more weight that needs moved the more fuel it is going to consume.  One source even says for every 100 extra pounds in a car, there is 1-2% fuel efficiency is lost.

I drive a 2003 Civic Hybrid, which has this cool feature on the dashboard that allows me to see my instantaneous fuel economy.  While I don’t have any scientific evidence of this, I notice a much more considerable amount of effect on my gas mileage based on my tire pressure.  They say you should check your tires at least once a month, I would say more often if the weather changes frequently (like it does in Ohio this time of year).  Many of the sources have thorough instructions on how to check you tire pressure.

So with all this, there are three things to do:

1. Check the tire pressure for proper inflation.
2. Replace the air filter when recommended (most techs will check the filter for you when you get an oil change done).
3. Unload the car from shopping trips and any unnecessary items immediately.

Sources: NHTSA, AAA, FuelEconomy.gov