Don't Mess Up a Good Thing



Feel less guilty about your pollution-mobile: maintain it.

Lucky you: Today's cars are much cleaner than the ones your parents and grandparents drove. So driving today isn't quite the polluting experience it once was. But that's assuming you maintain your car properly -- you know, take it in for servicing like the manual tells you to do. Proper maintenance of all vehicles -- old or new -- makes them run better and cleaner, and cheaper. Mechanics today are highly trained to make sure your car performs at its best. They need the training: cars' onboard computer powers are awesome! Properly maintained, cars of today will serve you well. Engines in modern cars last longer than those of 30 years ago -- despite what Uncle Jack says about his 1967 Ford Galaxie!


Here's what good maintenance means.

First off, good maintenance means understanding something about how your car works. When you understand what's going on under the hood and puffing out the tailpipe, you'll do everything the manual asks you to. Cars are modern-day miracles, yet we take them for granted. Don't. Treat the beast with care and respect.

Meet your car's engine: a Socratic dialogue.

Q. How does a car work?
A. The engine makes it go.

Q. What makes the engine go?
A. Lots of explosions.

Q. What kind of explosions?
A. Explosions caused by the gas you just bought at the convenience store.

Q. Why doesn't the gas explode as soon as I put it into the gas tank?
A. It needs a spark to ignite it.

Q. Where does the spark come from?
A. From a spark plug. A spark plug converts electricity into a spark that ignites the gas that gets pumped into the cylinders of your car's engine.

Q. Why does an engine need cylinders?
A. An engine must contain the explosion of the gas so the explosion can be turned into useful energy.

Q. How does a cylinder do that?
A. The force of the explosion makes a piston in the cylinder jump back -- just like a cannon ball coming out of a cannon when the powder is lit and explodes.

Q. So the piston jumps back. Then what?
A. The pistons are connected to the crankshaft, which is connected to the transmission, which is connected to the wheels. Vroom!

Q. Pistons? How many pistons does a car's engine have?
A. A car's engine has as many pistons as cylinders. Most cars' engines have four or six cylinders. Bigger cars may have engines with eight cylinders.

Q. So, the more cylinders an engine has the more powerful it is?
A. Generally, yes. Power depends on both the number of cylinders and how big the cylinders are. Engines are often described as "fours" (four-cylinder) or "sixes" (six-cylinder), with, say, 2.2 liters of displacement. (Cubic inches were once used to describe the size of cylinders, but now metric measurements are standard.) The bigger the displacement, the more power -- just like a canon.

Q. What's all that extra garbage under the hood of my car? The engine on my lawnmower is a lot simpler.
A. That "garbage" is actually the engine's electrical system, fuel system, cooling system, lubrication system, and exhaust and emissions system. If your car's engine were like the engine on your lawnmower, it would be loud, inefficient, hot, dirty, shaky, and not very powerful. It'd be like a go-cart with a ton of bricks on top.

Q. So where does maintenance fit in?
A. You're asking a car's engine to do a lot. In 10,000 miles of driving, consider what's happening:

(information from the "Nutz & Boltz" car show Web page)

Q. What maintenance work should be done?
A. No guesswork here. Follow the manual that came with your car. Look in the "Service" or "Maintenance" section and you'll find charts that describe what maintenance must be done when. Simple things you can do yourself on an ongoing basis include:

Q. Taking my car in for service costs money. What's the payback?
A. The Car Care Council, an auto industry trade group, has calculated you could be wasting at least $150 a year in fuel costs if:

Even more important than the money issue are the issues of safety and reduced exhaust emissions. An underinflated tire can blow out and cause an accident. An engine not tuned properly pollutes more than one that is -- plus you waste gas and your car doesn't run like it should. And poor maintenance can lead to serious and expensive problems (such as toasting your catalytic converter).

Q. Is any special maintenance required for my car's emissions system?
A. The most important maintenance for your car's emissions system is regular engine maintenance, including periodic oil and filter changes. If an engine is running properly, the emissions system will do its job. The workhorse of your car's emissions system is the catalytic converter, which is designed to last the life of the car. Several other anti-pollution mechanisms are checked during routine servicing and sometimes replaced: the PCV (positive crankcase ventilation) valve, which regulates recycling of partially burned gases and vapors; and the EGR (exhaust gas recirculation) valve, which uses exhaust gas to regulate combustion temperatures in the cylinders. The "oxygen sensor" in the exhaust system may also have to be replaced at some point; it must be checked when one of those red lights on your dash that says "OXS" or "Maintenance" comes on.

Q. Does a catalytic converter really last a car's lifetime? I heard it's no good after five years, and that you might as well disconnect it.
A. Catalytic converters are designed to last the life of the car. If you stick to your car's regular maintenance schedule, you shouldn't have any problems. If the catalytic converter does fail, it must be replaced. UNDER NO CIRCUMSTANCES CAN YOU DISCONNECT YOUR CAR'S CATALYTIC CONVERTER OR ASK A MECHANIC TO DISCONNECT IT. IT'S AGAINST FEDERAL AND VERMONT LAW. PUNISHMENT FOR BREAKING THE LAW INCLUDES A FINE OF UP TO $2,500 FOR INDIVIDUALS AND UP TO $25,000 FOR MECHANICS.

Q. My mom's new car has a yellow "idiot" light on the dashboard that says "check engine." Should I worry if it comes on other than when I start the car?
A. You bet. When the light comes on (other than when you start the car), it means something's not working with the engine, including the emission controls. The car will still run when the light comes on, but continuing to drive it may cause serious damage. Problems can sometimes be pinpointed by using "OBD" -- on-board diagnostics, which are done by plugging your car into a computer. You'll hear more about OBD as part of new inspection programs being implemented in Vermont.

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