Vehicles with properly maintained engines and emission control systems pollute less and are more fuel efficient. Well-maintained vehicles perform better, last longer, have higher resale values, and save you money. Although regular vehicle maintenance remains very important, high emissions from newer vehicles usually result from a system malfunction that must be diagnosed and corrected by a trained technician.

Worn tires, defective brakes, loose steering, and inoperative lights are among the conditions that lead to highway accidents.

 Here are some tips to keep your car running properly while reducing air pollution:

• Follow the manufacturer's maintenance guidelines. The owner's manual for the vehicle provides recommended maintenance intervals and product specifications. Following these recommendations helps identify any problems before they cause more serious ones.
• Have your engine and emissions system checked promptly if you notice a change in the way your vehicle functions, fuel efficiency drops, a warning light goes on, or the vehicle fails an emissions test.
• Change the vehicle's oil regularly. Follow the manufacturer's recommendations about which oil to use. Most motor oils have an energy conservation label indicating that they improve fuel efficiency by reducing engine friction. When adding oil, don't overfill the crankcase; the extra oil is consumed more rapidly than necessary. If you change your own oil, don't mix the used oil with other substances and don't dump it into a sewer or on the ground where it can contaminate water supplies.
• Have the fuel injection system checked per manufacturer’s recommendation. Fouled fuel injectors reduce fuel efficiency, make the vehicle more difficult to start and drive, and significantly increase pollutant emissions. Most gasolines sold today contain additives to control deposits that foul fuel injectors.
• Change the air filter as often as the manual recommends. In between changes, inspect it by taking it out and tapping it against a hard surface. If dirt falls out, replace the filter.
• Keep your tires properly inflated. The Department of Energy states that if all tires were properly inflated in the United States, about 4 million gallons of gas could be conserved every day. Underinflated tires can reduce gas mileage by 1 mile per gallon. You may have noticed that more energy is required to ride a bicycle when the tires do not have enough air. With a car, more gas is required when the tires do not have enough air. Use a pressure gauge and check the pressure of your tires every two weeks. Maintaining the proper pressure saves money, reduces pollution, and is safer. Check to see if there are any cuts or bruises on the sidewalls. Is there sufficient tread? (Use a penny, Lincoln’s head down, to check tread depth. If Lincoln’s entire head remains outside of the tread, depth is less than 2/32" and the tire should be replaced.) Tires are generally replaced in pairs or sets of four. Check to see if all the tires are worn evenly.
• Check the antifreeze/coolant level weekly by observing the overflow tank. (Never remove the radiator cap unless the engine is cold!).
• Keep your vehicle tuned up. The gas mileage of most cars could be improved by as much as 6 percent with a minor tune-up.
• Check the headlights on your car to sure that all lights work and are aimed properly. Properly aligned headlights allow you to see the road and help other dirvers see your vehicle.
• Keep the brakes maintained so that you can stop quickly. This can help you avoid an accident. Make sure the vehicle stops straight and smoothly and does not pull to one side when the brakes are applied.
• Check the steering fluid. Make sure the vehicle does not pull to one side if you let go of the steering wheel.

Regular vehicle maintenance not only reduces air pollution and saves you money, but it can also prevent frustration if your city/state has an I/M Program. I/M tests use special equipment to measure the pollution in your car's exhaust system. The programs have been able to reduce air pollution by 30 percent in some states. In most communities, I/M is the best smog-fighting tool available, as well as one of the cheapest. For more information about your state's program, call your state's Department of Motor Vehicles or state environmental agency.

When you’re behind the wheel, you are responsible for how that vehicle gets you and your passengers safely from point A to point B. If either you or your vehicle are unable to do this you may not make it to point B. In addition to losing your driving privilege, an accident can cost you and others a lot of grief and money. Much worse, it could cost lives.