Spark plug wires, also called high-tension wires, deliver electricity from your car’s electrical system into each spark plug. The spark plugs, in turn, deliver charge to the combustion chamber, which results in the burning of fuel. Without a spark plug, your car’s engine will not run. A bad high tension wire can result in inefficient fuel burn or misfires. In some cases, your car might not even run or start at all if one of the spark plug wires is not transmitting electricity properly.
Oftentimes, a tune up, oil-change or spark-plug change will not necessarily include a spark plug wire change, unless you specifically ask for it. Changing your spark plug wires is an activity you can do yourself, though, with enough know-how and the right tools.
- Head to the auto parts store and buy a set of spark plug wires. These are best bought as a set, and will come in sets of three or four, depending on your engine configuration. For example, an inline-4 engine will need 4 spark plug wires. A V6 will require two sets of 3 spark plug wires.
- While you can replace just one spark plug wire, it’s usually best to replace the entire set, because different wires might produce inconsistent electricity flows, which are not good for your engine. Note that spark plug wires have different measurements, as each wire is meant for a specific spark plug in series.
- Open your hood and prop it up. It’s usually best to work on your engine in the morning or after you have parked it and let it cool for about two hours. Otherwise, you can use protective gloves to protect your hands against the heat of the engine.
- Pull out the spark plug wires from the spark plugs. You can use a spark plug wire puller. But since these are simply stuck onto place by the rubber insulation, you can easily pull them out. Pull them at the base, and not from the wire.
- Pull out the spark plug wires from the distributor cap. Note the sequence of the wires. It’s best to write these down on a piece of paper.
- After removing the set of wires, you can transfer the clamps or clips to the new set, so these can be easily clipped in place on the engine.
- Attach the new wires to the distributor cap. Remember the sequence that you noted earlier. When you plug it in place, wait until you hear a soft click or pop, which means the wire is properly seated.
- Attach the wires onto their respective spark plugs. Again, listen for the soft clicking sound.
- If your car has a coil wire, replace it. This goes from the center of the distributor cap toward the coil. Much like the spark plug wires, you will have to wait for a soft pop, which should indicate that it’s seated firmly in place.
- Start your car and check if the timing is right. On most fuel-injected vehicles, timing is electronically controlled, so you will not need additional adjustments.
When changing spark plug wires, invest in good quality wires, as this will have an effect on how efficiently your engine runs. You don’t want to have inefficient or unequal burn, which will result in dirty exhaust fumes, and which might result in engine trouble in the long run.