What do spark plugs do?

Spark plug

Spark plugs are a key component in your vehicle’s ignition system. Every time you turn the keys in your petrol engine car, the spark plugs create an electrical spark that ignites the air/fuel mixture inside the vehicle’s engine. This allows the car to start successfully.

Like many other vehicle parts, spark plugs can wear out over time and require replacement. Spark plugs contain materials that allow a spark to ignite in your engine’s combustion system. When these materials wear out, your spark plugs will become less effective at creating an ignition in your engine combustion chamber for each cylinder. Although car manufacturers have greatly improved the lifespan of spark plugs, they can still encounter problems, affecting your vehicle’s ability to ignite fuel properly.


What are the different types of spark plugs?


Copper-tipped spark plugs are the cheapest, most common type. Copper spark plugs have the shortest lifespan. This is due to copper eroding over time. The strength of a copper-tipped spark plug lies in its ability to conduct electricity more quickly and efficiently than any other material.

The high heat conductivity of copper allows the spark plug to stay cooler than some other types, preventing overheating and damage to the spark plug in extreme conditions.



Platinum-tipped spark plugs have a much longer lifespan under standard driving conditions. This makes them a preferable option for most drivers. Unlike copper, platinum doesn’t erode over time. This means that you can expect a platinum-tipped spark plug to last twice as long as a copper-tipped plug.

Platinum spark plugs are more expensive than copper. This is because platinum is a much rarer naturally occurring element. Platinum also lacks the high conductivity that copper offers.



Iridium-tipped spark plugs are the most expensive. However, they allow superior fuel combustion. This results in a smoothly running engine that will stand the test of time.

Iridium spark plugs offer a longer lifespan than copper spark plugs, but may not last as long as a platinum spark plug.


What are the signs of damaged spark plugs?

1. A misfiring engine.

A misfire occurs when your vehicle’s engine misses a process in its combustion cycle, causing unburnt fuel to go into the exhaust. Misfiring is commonly caused by problems in a vehicle’s ignition system such as damaged spark plugs or ignition coils.

Your vehicle will lose power when it misfires. This may result in your engine vibrating. “Severe” misfires may cause a loud popping noise in your engine, sometimes accompanied by backfiring in your exhaust pipe or intake manifold.

Over time, misfiring can cause expensive damage to your vehicle’s exhaust system. Therefore, it is important to get your ignition system serviced earlier rather than later.


2. Lowered fuel economy:

A correctly functioning spark plug will allow fuel to combust correctly, maximising fuel efficiency. A damaged spark plug will not allow fuel to combust as effectively. When fuel does not combust correctly, your engine will demand a higher amount of fuel to reach healthy combustion levels.

If you find that you are using more fuel than normal, you should get your spark plugs examined. It will save you money over time.


3. Rough idling:

Idling is when your vehicle is running but not moving. If your vehicle’s engine is vibrating or producing rough, shaking noises while it is idling, it may be due to a worn spark plug.

While idling, your engine should run smoothly, producing a constant healthy tone and not shaking or stuttering. If you notice that it is exhibiting these symptoms, you should get your vehicle serviced. A vibrating engine can damage surrounding components, causing expensive damage to your vehicle.


4. Vehicle not starting:

In severe cases, a spark plug may become so worn that it is unable to give your vehicle the necessary energy needed to start. In this case, you will need to get it fixed or replaced by a professional.


Spark plug replacement services in Hamilton

At Grimmer Motors, we are able to diagnose ignition-related errors in any vehicle. This allows us to determine if the spark plugs are in need of replacement. Our team of highly skilled, qualified, and experienced mechanics can then acquire the correct spark plugs for your car and perform a spark plug change.

For reliable spark plug services or replacement in Hamilton, book an appointment with us today.

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