Cars-we can't live with 'em, and we can't live without 'em. On one hand, they represent independence and self-reliance. Cars let us go where we want, whenever we want. Behind the wheel, we're beholden to nobody's timetable or route map.

But, oh, the price we pay! Sure, today's cars emit far less noxious, smog-forming pollutants than their forerunners did even 10 years ago. Nevertheless, a typical car still spews 21,700 pounds of carbon dioxide, 195 pounds of carbon monoxide, 33 pounds of nitrogen oxides, 28 pounds of hydrocarbons and 3.3 pounds of very fine soot per year, counting tailpipe and fuel-cycle emissions. A sport-utility vehicle produces about 40 percent more of this breathable junk than a car.

As for fuel leaks, oil spills, solid waste and scrap-let's not even go there.

You live in the real world, though. You're not going to give up your car. You can, however, do your part to make it more Earth-friendly. And that means practicing "enviromaintenance." Now, in October (National Car Care Month), these 10 steps are a good place to start.
 
1. Keep your engine fine-tuned.

Ordinary fuel consumption accounts for a whopping 77 percent of the energy used over a car's life cycle, from manufacturing to disposal. So maximum fuel efficiency translates to maximum Earth friendliness. Follow the recommendations in your owner's manual for changing spark plugs, and attend to sluggish, rough-running,or high-idling engines ASAP.

2. Stop leaks pronto.

When you notice oil spots on your parking space, you might feel tempted to put off repairs. After all, it's cheaper just to keep an eye on the oil level and add some. But according to the U.S. Environmental Protection Agency, as little as a quart of oil can foul 250,000 gallons of water. Oil leaking out of your car winds up on the roadway, where rain washes it into storm sewers-and the water supply. A well-equipped shop can pinpoint leaks fast.

"We use a dye that glows under ultraviolet light to find pesky leaks you can't find with the naked eye," notes Michael Mulé of One-Stop Shell, an AAA Approved Auto Repair network station in Brooklyn. The same goes for power steering, transmission and other fluids.

3. Fight air pollution with air pressure.

According to one oil company estimate, Americans could save 4.2 million gallons of gas every year just by keeping their tires properly inflated. When was the last time you checked yours?

4. Recycle old oil.

The U.S. Bureau of Transportation Statistics reports that 1 in every 20 do-it-yourselfers pours his used oil down the drain or into the ground. That comes to 20 times more oil dumped in a year than the infamous Exxon Valdez spill. New York requires service stations and repair facilities to accept used oil from walk-in do-it-yourselfers. There's no charge, so there's no excuse. Re-refined motor oil becomes fuel oil and other useful products.

5. Recycle old coolant, too.

As one of nature's few sweet-tasting poisons, ethylene glycol-the active ingredient used in most antifreeze-presents a deadly temptation to animals. When you flush and fill your radiator, the old antifreeze (even the long-life kind) can be recycled. Chrysler, Ford and General Motors okay recycled antifreeze for their vehicles, provided the product meets certain specs.

"Service stations are not required to accept used antifreeze for recycling, although some might be willing if you ask," says Matt Burns of the New York State Department of Environmental Conservation. "Otherwise, you can save it for your locality's household hazardous waste collection or call your sanitation department."

And using propylene glycol-based coolant such as Prestone's Lo-Tox doesn't let you off the hook. Though less toxic than conventional antifreeze, it still contains metals and other nasty stuff leached from the car's cooling system. Never dump it in the ground or down the sewer.

6. Turn in batteries and tires.

Automotive batteries contain lead and sulfuric acid. Luckily, the state makes provisions for turning in old batteries, just like deposit bottles. When you buy a new battery, you pay a $5 "incentive fee," refundable when you turn in an old one. If you happen to have extra old batteries, retailers must accept up to two batteries per month from walk-ins, even without the purchase of a new one.

New Yorkers also pile up 20 million scrap tires every year-so many that the state has accumulated a 40- to 50-million-tire stockpile. To clean up that mess, you'll pay $2.50 per tire every time you buy new ones, beginning Oct. 1. (Actually, only part of this fee goes into a scrap-tire fund; some goes into the general fund, but that's another sad story.) And, when you buy a new car, you'll pay $12.50 more-$2.50 per tire, including the spare. Scrap tires can be shredded into playground padding and other civil engineering uses.

If your lawn décor includes a few old tires lying around, remember that water collecting inside becomes an ideal breeding spot for mosquitoes carrying West Nile virus and other diseases. Get rid of them. To find out where, call a tire retailer or your local Department of Environmental Conservation.

7. Change your air filter.

A dirty air filter can decrease your gas mileage (and thereby increase pollution) 10 percent. Change it at least every couple of years. It's easy and cheap to do yourself, even if you're all thumbs.

8. Consider rebuilt and used parts.

Rebuilt alternators, starter motors, transmissions and other replacement parts often come with warranties almost as good as new ones. Besides, they're usually less expensive. For some collision repairs, used parts may also offer a cheap, acceptable alternative to new ones. Otherwise, this stuff ends up in landfills.

9. Ease your trigger finger off the pump.

In terms of smog-forming hydrocarbons, every gallon of gas you spill equals 7,500 miles of driving. The splishes and splashes that hit the ground when you overfill your tank add up. When the automatic shut-off pops the nozzle during a fill-up, don't risk squeezing out a few more cents' worth.

10. Use accordion nozzles when you can.

All gas pumps in the New York City area have "vapor recovery" nozzles-the black, accordion-like plastic gizmos on the business end of the hose. They trap gasoline vapors, which are hydrocarbon pollutants. But some pumps upstate (a different air quality zone) may not have them. Patronize stations with vapor-recovery pumps when you have a choice.