How To Stop Spark Plug Wires From Arcing: Reasons & Prevent

How To Stop Spark Plug Wires From Arcing

Those who notice spark plug wires arcing in their vehicle often become tense about the issue as it can lead to engine failure. If this issue makes you wonder why this arcing occurs and how to stop spark plug wires from arcing, we’re here to help you out.

Reasons Behind Arcing of Plug Wires

The spark wires of any vehicle ensure the essential flow of electricity in all the cylinders of that vehicle. If these wires turn out faulty or installed incorrectly, these create electrical arcing when getting in contact with each other.

So, what causes spark plug arcing? Let us go through the main reasons for arcing so that dealing with and preventing the issue gets easier for you.

1. Defective Wires

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Plug wires might have several defects, including bad ground connection, cheap insulation, and excessive impurities. Any of these can make the plug wires defective, and create arcing in certain conditions.

2. Poor Ground Connection

There is a connection between the ignition coil and the spark wires. The produced voltage should go through the plug wires to the coil, and it is only possible when the ground connection is stable.

But in case of having a poor connection, the voltage can’t get back, and thus you might see sparks coming from spark plug wires.

3. Unstable Electrical Connection

If the wires get an unstable electric supply from the battery, the plug wires can create arcing. Often you might notice spark plug arcing outside because the electrical flow is not simultaneous in case of an unstable connection.

4. Weak Ignition Coil

An unstable or weak ignition coil can’t get along with the large voltage that flows through the plug wires. Because putting up with the voltage is necessary for jumping off the plug gap.

When an ignition coil struggles to maintain the voltage, the coil provides low voltage through an easy and alternative path, and thus the plug wires create arcing.

Preventing the Plug Wires from Arcing

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If you notice any spark plug arcing symptoms like an increase in fuel consumption, engine knocking, a decrease in acceleration power, engine misfiring, and backfiring, then you must take necessary measures immediately.

Some convenient ways and techniques for preventing electrical arcing are discussed below.

1. Removing and Replacing the Ignition Coil

Most of the time, the weak ignition coil is the main cause of electrical arcing. If the ignition coil remains unnoticed, it can provide low voltage through an easily accessible path. Besides, the coil might get overheated or create a leak. It is necessary to remove the weak ignition coil and replace it with a new one.

2. Testing the Wires

If the plug wires turn out faulty have wrong wire routing, overheating, or have poor insulation, it is necessary to change the wires and get new ones.

So, you need to test the wires of your vehicle regularly so that the wires do not remain unnoticed. Be sure to carry a plug tester for proper checking.

Related: How To Test A Spark Plug With A Battery?

3. Proper Cleaning

To keep your vehicle’s plug wires safe and free from electrical arcing, there is no alternative to a proper cleaning process. You can use a hard-bristled brush for removing the outside fragments and a soft cleaning napkin to clear off the dust particles. Make sure you remove the lead from the plug wires before cleaning.

4. Regular Check-Ups

Each component and part of your vehicle are prone to damage as these mostly deal with high voltage and current. It is necessary to check up on the components regularly.

You will be able to notice if there’s any damage or malfunctioning of the plug wires or coils, and you can resolve them without any delay.


What should be the distance between plug wires for preventing arcing?

The distance between the plug wires should be greater than the plug gap. Otherwise, there is a possibility of electrical arcing.

What is ignition coil arcing?

The ignition coil ensures high voltage current flow to the plugs, which is essential for the combustion of gases in the cylinder. When this coil leaks, it creates ignition coil arcing.

Is temperature related to electrical arcing?

Temperature affects arcing as electrical leakage generally occurs in high temperatures. When the temperature goes crazy high, it makes electrical charges jump and causes arcing.

Is it necessary to replace plug wires to prevent arcing?

If you replace the vehicle’s plug wires properly, arcing will not occur.


Resolving any issues regarding the electrical arcing of plug wires gets easier if you know how to stop spark plug wires from arcing. Take necessary precautions and apply the techniques stated above to avoid electrical leakage that might affect the performance of your vehicle.

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2 thoughts on “How To Stop Spark Plug Wires From Arcing: Reasons & Prevent”

  1. hi i have a knock sensor code on my toyota camry changed out sensor and others and had computer repaired. just changed out wires because i could see arking. could this have set off knock code and can i drive it a few cycles and the cel light may go off. tnx cliff

  2. I have a 57 Chevy arching across terminals replaced coil cuz cracked 3 times plus changed coil wire to distributor it has petronics no points cant figure out why arching

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