Replacing Spark Plug Wires Is As Easy As Pie

Spark Plug Wires Ignition Wire Set 1 photo
They may look like your average wires, but spark plug wires have a very important job to do. Their mission is to provide electricity from the car's 12 volt battery to the engine's spark plugs. Without spark plugs doing their thing properly, the engine will misfire.
While modern vehicles are fitted with iridium or platinum spark plugs that can last at least 60k miles, the standard copper plugs of older cars are good for 10k to 20k miles. However, most of the time, spark plug wires will give out before the actual spark plugs due to engine vibration abrasion, jacket wear, spilled fluids or repeated disconnections/reconnections.

Those of you that currently drive or have owned an older car might've been in the following situation: it's morning, you get in your beat-up oldtimer, start it, then leave for work. Though you know a car as old as that is a little rough at idle, you push the accelerator pedal at circa half-throttle and you feel the motor misfiring. Why's that? There are lots of potential causes, of course, but most of the time it's a problem with spark plug wires wear & tear. Most often it's a case of electrical leakage: not enough zap to the spark plugs equates to rough fuel-air mixture ignition.

In this case, you'll need to replace them worn wires with a set of new ones. For a four-cylinder engine, premium quality kits can be found at the shops or on Amazon for under 50 bucks excluding spark plugs, so it's not that big of an investment. With great fortune for those a little shy with a spanner, we're happy to inform you that replacing spark wire plugs is not a difficult thing to do. Before starting, don't forget to disconnect the negative battery cable and do the operation with the engine thoroughly cool.

First, two warnings: don't go for "high-performance" wires and don't just yank the old wires out by hand. Grasp the boot at the plug end or use an inexpensive tool known as boot pliers to remove stuck spark plug wires. Don't forget to remove spark plug wires one at a time. Just number the wires with tape in order to remember what wire goes where with the replacement set.

If the new set of spark plug wires doesn't have little plastic guides, we'd recommend to put the old set of wires on a table next to the replacement set and match up which of the wires goes where according to length. After you've figured out which wire goes where, it's time to pop in the new ones in place, one at a time. It's very easy to plug in the new wires badly, so be careful and listen carefully: if the plug wire makes a quiet "pop" sound when inserting it on the spark plug, that's the sign you did a good job. Told you it's easy!
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About the author: Mircea Panait
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After a 1:43 scale model of a Ferrari 250 GTO sparked Mircea's interest for cars when he was a kid, an early internship at Top Gear sealed his career path. He's most interested in muscle cars and American trucks, but he takes a passing interest in quirky kei cars as well.
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