When to replace the spark plug wires?

The spark plugs are divided into two categories, namely: spark plugs, used for petrol engines and incandescent spark plugs, for diesel cars.

Spark plugs are essential components for the proper functioning of the car, because they have the role of igniting the mixture of air and fuel and to initiate combustion at the level of the cylinders.

To fulfill its function, however, the spark plug must be connected to the power supply. This connection is ensured using spark plug wires or plugs.

As a reminder, we are going to tell you that the incandescent spark plugs only work (generally) within the first 5 minutes after starting the car. They do not ignite the fuel by sparks, but they burn their peaks up to 800 degrees Celsius (1472 degrees F), in this way the combustion chamber is heated to the optimum self-ignition temperature.

Compared to the spark plugs that are active throughout the engine’s operation, with the role of igniting the gasoline-air mixture at each piston cycle, the incandescent spark plugs have a single role: starting the diesel engine when it is cold.

Spark plugs, consumable components essential for the smooth running of the engine

As a result of the prolonged use and the appearance of the normal phenomenon of wear, the wires at the level of the spark plugs can be damaged in time. If this damage occurs, it results in the transmission of an improper electrical charge to the spark plugs, which causes the engine to malfunction.

The most common problems that may occur include higher fuel consumption, low engine power, a “suffocation” of the engine when idle, increased risk of failure or even engine shutdown.

How often do spark plug wires need to be changed?

In order to determine the exact frequency, it is good to consider a very important aspect, namely the age of our car. The age of the car is important because the vehicles manufactured after a certain period are no longer equipped with spark plug wires. In this case, a coil is used on the spark plug, these coils are particularly efficient in terms of long-term use.

But even if your car is equipped with spark plug wires, you should know that the newer the model of the car is, the more performance technology, which means a much-improved service life.

How long do spark plug wires last?

How often do spark plug wires need to be replaced

On average, we can say that these wires should have a lifetime of over 50,000 km (31.000 miles), thus exceeding the estimated lifetime of copper spark plugs. Certain factors contribute to the influence of the state of these cables, factors that you should know.

How to recognize spark plug wires?

The appearance of spark plugs wires

To properly assess the condition of such wire, it is easiest to inspect them in terms of appearance. If you notice a problem of isolation or changes to the normal appearance that could lead you to a possible deterioration, it is advisable to replace them even before the number of km/mils mentioned above.

 Spark plug wire types

If the wires have a high performance, it is good to know that the high-performance spark plugs will require much more frequent replacement (from about 50,000 km to 65,000 km, respectively, 31000 – 41000 miles).

The resistance level of the spark plug wires

The most efficient method of evaluating the necessity of changing these cables is resistance testing. An ohmmeter will be required to test the resistance. Check the information available in the technical book of your car to see what the standard values ​​of resistance are. Then test each cable separately to find out if the read resistance is within the known standard limits.

If higher resistance values ​​are obtained for an individual sheet, you must consider changing because it is a sign of incorrect operation. It is good to follow the advice of the specialized personnel regarding the maintenance of your car and carry out periodic checks.

These checks can save you from much higher expenses in the long run, as a low-cost failure can cause you to make large investments of time and money if you resolve it early.

How much does it cost to replace the spark plug wires?

How much does it cost to replace the spark plug wires

Costs of replacing the spark plug wires with the labor included are often between 120 $ and 400 $ depending on the care make, model and year of manufacture

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