Car PartsSpark Plug Wires

Aftermarket & OEM Spark Plug Wires

When is it time to replace your spark plug wires?

Over time, your spark plug wires will eventually fray and wear out. The operating temperature of your engine typically hovers around 200-degrees Fahrenheit, and that is enough to gradually stress the insulation around the wire and the connectors. This inhibits the successful transfer of voltage necessary to maintain proper ignition timing, and the engine will lose power. It will start to present itself slowly with an infrequent misfire in one of your cylinders, but once your spark plug wires start to deteriorate the snowball effect occurs. Pretty soon there will simply be no detonation in one cylinder entirely, and you'll be straining to get from place to place. Preventing this, however, is easy; and if you think you may have a bad spark plug wire, you can perform a couple of simple tests to make sure. The first thing you should do is visually inspect the wire for cracks or brittle spots. You can also run a thin, damp rag along the wires to feel for any cracks. If everything looks and feels okay, then you can try to listen for pops and crackles coming from your spark plug wires while the car is running. The last test is a resistance test, and you would need to measure the loss of ohms from one side of the wire to the other. Normal loss is between 10K and 15K ohms per foot of cable. If there is more loss then the wire is probably frayed at one point and the current is effectively being bottle-necked. Replacement spark plug wires are needed.

Spark plug wires are older and stronger than you think.

New Spark Plug WiresFrom the early days of automobiles, a consensus was made between automakers that mechanically timed ignition was the most cost-effective and reliable way to maintain accurate detonations. This system was composed of a distributor that was driven from the camshaft, an ignition coil that relayed power from the battery through the distributor, and the spark plug wires that delivered current to each spark plug. All of these components must be functioning in unison for your engine to be running properly. Modern spark plug wires are insulated with silicone or EPDM rubber to protect from engine heat. If the insulation on the wires is old and brittle, there is a chance for arcing of the electricity to another component. This tends to be the most common form of failure for spark plug wires, which is why they should be checked and changed if discovered to be damaged. On some vehicles, an ignition coil is mounted directly on top of the plug and connected to the ignition control module via an engine wire harness. This system has gained in popularity since the wire harness does not need to be changed regularly, thus rendering spark plug wires unnecessary.

An important, but easy job.

Changing spark plug wires is super easy, and usually takes only a few minutes. On occasion, replacement can be difficult if your access to the spark plug is blocked by other components. If so, let a mechanic do the work. You can also replace your spark plugs at this time too, since you're working right there.
  • First, locate the distributor or coil pack where the spark plug wires are connected. Then follow each wire to the spark plugs. These are located in the cylinder head(s), and should be easily visible.
  • The connectors at each end of the spark plug wires will simply pull off. They should not be difficult to remove. But before you do this, label each wire with the number of the cylinder where it was located. You will need this information later.
  • Once you have pulled the wires off the spark plugs and the distributor or coil pack, note the condition of the connector at each end. If you see corrosion, you should clean the component it was connected to so that the new wire will work most efficiently.
  • Next, take each individual spark plug wire and note its length. You will want to match the wires of identical length to the corresponding cylinder (thanks to your label). It is recommended you put a little bit of dielectric grease at each end so that moisture cannot penetrate it in the future.
  • Finally, connect each spark plug wire to the appropriate position on the distributor or coil pack and to the spark plug at the appropriate cylinder.

Not all parts are created equal.

Replacing your spark plug wires is just as easy of a process as buying them. However, there are so many brands out there that it is hard to tell what's good and what's not. At Car Parts Discount, we carry top quality spark plug wires meant to last as long as, or longer than, your original equipment. You can find great aftermarket manufacturers as well as low-cost brands for the buyer on a budget. So whether you want a set of performance spark plug wires or just need a set to get your car back on the road, we've got you covered with great pricing and fast shipping. Don't delay; order right away.

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