Smoke signals

What tailpipe emissions can tell you

If you visit a doctor regularly, you’ve likely had to submit to the awkward ritual of peeing into a tiny cup to help pinpoint any health problems.

Increasingly, Canadian motorists are faced with the automotive equivalent of a urine test in the form of mandatory emission testing. British Columbia’s AirCare program for motorists in the Lower Fraser Valley has been running since 1992 and, on April 1, 1999, Ontario launched its Drive Clean program in the Greater Toronto Area. After running a two-year pilot project, the Quebec government is still pondering whether it will introduce mandatory emission testing. A decision is expected next year.

Although the goal of cleaner air seems noble enough, critics of such programs have argued the result is to clean out drivers’ wallets with repair bills, testing fees and even new car purchases.

However, skilled mechanics know that each tailpipe has a tale to tell, if you can decode the clues. Just as a urine test can yield valuable data to a doctor, an exhaust-gas analysis test can tell if an engine is in peak condition. Many a costly used car horror story could be avoided if prospective buyers made the purchase conditional on a thorough mechanical inspection, including an exhaust-gas analysis.

Unfortunately, because sophisticated emissions-testing equipment can cost $60,000 or more, not all garages will invest in it. But just as you don’t need a medical degree to know that blood in the urine is a bad sign, drivers can learn to spot serious signs of trouble simply by tailpipe clues. The warning signs can also steer you away from a used car on the road to major surgery.

White smoke can be a sign of impending doom. While some white smoke is normal, particularly in cold weather, too much means big trouble. “Lots and lots of white smoke, especially if it’s sweet smelling, means you’re burning coolant,” says Rob MacGregor, chief instructor in the automotive department of the British Columbia Institute of Technology. Likely culprits are a leaking head gasket or cracked cylinder head. Left untreated, coolant could mix with the oil and destroy bearings or the car could lose enough coolant to overheat. Either way, it can kill your engine.

“It’s a major mess,” says Peter Lokun, coordinator of the General Motors automotive service educational program at Centennial College in Toronto. Drivers can inflict added damage by continuing to drive an overheating car. While some failures are the result of automakers’ manufacturing defects, maintenance can also play a role. Drivers should regularly check their coolant level (when the car is cold) and change the oil and coolant at the specified intervals.

Blue smoke is a sign of burning oil. “If it puffs blue on start-up, it’s the valve seals and guides. If it puffs blue on acceleration, it’s the piston rings,” notes MacGregor. “Either way, it’s expensive.” Motorists are looking at a four-figure fix. The problem may be a symptom of a worn-out engine or poor maintenance. “It could be caused by not changing your oil enough or not using the right oil,” says Lokun.

Black smoke is a sign that the fuel mixture is too rich. “It could be $2 to $2,000 to fix,” says MacGregor. The problem could be as simple as a clogged air filter or it could be a costly failure of the fuel-injection system. In older cars, a vehicle may simply need a carburetor adjustment. To prevent fuel system problems, drivers should change their air and fuel filter regularly, avoid “running on empty” and use gas-line antifreeze in the winter.

MacGregor says that while some B.C. drivers initially resented the AirCare program, motorists now boast if a vehicle is “blowing zeros” on the test. “People should remember that the cleaner a car is running, the more efficient it is,” he notes. “Otherwise, you’re just throwing away money on gasoline. In the long run, what’s good for the environment is good for your wallet.”

Lokun is even more blunt. “If you own a dog, you’re supposed to clean up after it. If you drive a car, you should clean up after it too.”

Maryanna Lewyckyj is consumer advocate for the Toronto Sun. She conducts car care seminars for women through her company, Autophobics Anonymous.

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