It's time to check your pesky spark plug wires

Spark plug wires are pretty durable. They aren't a moving part so they don't wear out too often.

But a damaged spark plug wire can make your car run rough and affect gas mileage. That's why a careful inspection of your plug wires can avoid any problems.

And a good time to check your wires would be while you change your spark plugs. So do a quick inspection and save yourself some headache. Here's how:

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Open the hood and locate the spark plug wires. They can be black, blue, red or orange. Most are black. The number of spark plug wires most often corresponds to the number of cylinders your engine has.

Don't take all the spark plug wires off at once. Remove the spark plug wires one at a time. They must go back on the distributor cap in exactly the same order they came off, or you'll have changed the "firing order" and your car may run badly or not at all. You can cause expensive damage by switching the order of the plug wires.

With your engine off, start at the distributor end of the plug wire and work your way toward the plug end. You're looking for anything that is not smooth, pliable rubber.

Bend the wires slightly to be sure no cracks appear. Cracked wires can cause misfires resulting in poor performance.

Check the boots at the distributor end of the wires to be sure they are not torn or cracked.

Finally, check the wires at the spark plug end one at a time by pulling it off the plug and inspecting the end for any tears or cracks. Also look to be sure there is no burning or darkening of the end.

If you find any damage, it's time to buy a new set. They can be as little as $20 or as much as $100+ for a set depending on your application. It's worth the cost, though. A bad plug wire can be a little monster and it can even trigger your Check Engine Light.

Spark plug wires should be changed when they start to become hard or inflexible, or look dry and cracked. If one wire fails, it's probably time to change them all. Spark plug wire life varies greatly depending on a number of factors, but you should change them at least as often as manufacturer's recommendations.

For more info on spark plug wire maintenance, visit www.borgwarner.com.