Hidden time bombs

How to defuse car problems that can flare up without warning

By Maryanna Lewyckyj

December 16, 2003

Some symptoms of vehicle woes are about as subtle as a siren. A tooth-rattling ride or glowing dashboard lights are obvious red flags. But some car troubles can arise with little or no warning. Learning to spot these sneaky hazards before you get behind the wheel can save you big bucks and keep you safe.

"You have to learn to distinguish between nice-to-do repairs and need-to-do repairs," says Fleur Govaerts, an automotive-service instructor at Centennial College in Toronto. "It pays to get to know the big problems."

Beat the timing-belt blues

Imagine riding a bicycle uphill and having the chain fall off. No amount of pedalling will propel you until the chain is fixed. Hidden in the bowels of your engine is a part that's just as critical to your vehicle: the timing belt or timing chain. Both devices synchronize the movements of the engine valves and pistons. If the belt or chain breaks, the engine can no longer generate power; the car will coast to a stop and need to be towed.

Most cars have timing belts that must be changed regularly, usually every 60,000 to 100,000 kilometres. Timing chains are more durable, but their replacement intervals vary depending on the vehicle's manufacturer. Belts and chains can fail without warning and cause major engine damage. Ignore the replacement intervals stated in your owner's manual and you may be shelling out thousands of dollars for an easily avoidable repair.

Dodge joint damage

If you own a front-wheel-drive vehicleâas most drivers doâit's equipped with constant velocity (CV) joints. These flexible couplings allow the drive axle to rotate and flex when the car turns or hits a pothole and are packed with grease and encased in boots (rubber covers with accordion-like ridges). After 100,000 to 150,000 kilometres, these boots tend to crack and tear, allowing lubricants to seep out and harmful dirt and debris to creep in.

Spot the problem early and you'll only need to replace the boots and grease. Ignore it and the more expensive metal innards will fail, causing the repair cost to balloon. The telltale sign of CV joint trouble is a clicking sound when turning corners, but you'll want to catch the problem before you can hear it. The best defence is to have CV boots checked every 10,000 kilometres.

Battle blowouts

If a tire blows at highway speeds, you may not get a second chance to learn how to head off such a calamity. High-speed blowouts are one of the most dangerous automotive failures. Since low tire inflation is the leading cause of blowouts, it's best to check your tire pressure at least once a month. Also, make sure to check for uneven tire wear. If both shoulders of a tire are worn more than the centre, it's a sign of chronic underinflation. As well, inspect the tire's side wall for cuts or bulges, which can weaken it.

Avoid head-gasket headaches

If your car blows a head gasket (the seal between the top and bottom parts of your engine), you may have trouble keeping your cool when you get the four-figure repair estimate. Head-gasket failures aren't common, but some used cars are notorious for them. Phil Edmonston's Lemon-Aid series of car-buying books can help steer you away from the worst culprits.

The most obvious sign of head-gasket doom? Huge cloudsânot just little puffsâof white exhaust smoke on acceleration. Other symptoms include a falling coolant-reservoir level and rising oil-dipstick level. Poor upkeep can hasten a head gasket's demise. Always change your coolant at the intervals stated in your owner's manual.

Maryanna Lewyckyj is the Toronto Sun's Consumer Alert columnist. She conducts car care seminars through her company, Autophobics Anonymous.

GET CHATELAINE IN YOUR INBOX!

Subscribe to our newsletters for our very best stories, recipes, style and shopping tips, horoscopes and special offers.