Everything You Need to Know about Spark Plugs in a Car
Spark plugs may be small in size, but they have a big role to play. Quite often, a bad spark plug is the reason your car doesn’t start properly – and that’s when you need to replace them. Today, we will take a look at how spark plugs work, how they are replaced and, most importantly, when do they need to be replaced.
How Do Spark Plugs Work?

Simply put, spark plugs in a car are responsible for starting the engine. As the name suggests, these plugs emit a spark of electricity across a small gap, creating the ignition needed to start your vehicle. The engine starts when the engine’s pistons come in motion due to the heat transferred by spark plugs.
These plugs are located at the top of the engine’s cylinder head. Once they spark, your engine powers up, producing a smooth burn of the compressed air-fuel mixture. The plugs are also responsible for burning off deposits produced by fuel additives and other toxins.
While they may seem small, spark plugs in a car are built to survive extreme heat and pressure. They are quite resilient, but you will still need to replace them after a while.
How Many Spark Plugs Does My Car Require?
This depends on the size of your car’s engine. A four-cylinder car will generally have four spark plugs. A six-cylinder engine car usually has six spark plugs, an eight-cylinder engine has eight spark plugs and so on. However, in some cases, the number of plugs is doubled. For instance, a HEMI engine has two spark plugs per cylinder.
Do I Need to Replace My Car Spark Plugs?

Generally, spark plugs can go for many kilometres and don’t need to be replaced very often. However, it is important to know when to change the spark plug as you can face several issues due to bad spark plugs:
- Your car doesn’t restart easily. It can be because of faulty spark plugs that aren’t powering the engine properly.
- The fuel economy of your car is compromised, and the tank needs filling more often. Old or worn-out spark plugs won’t burn the fuel entering the engine effectively.
- Your engine will make a lot of rattling noise due to bad spark plugs.
- The car will not accelerate smoothly. If the plug doesn’t give a 100% fire spark when you accelerate and change gears, the vehicle performance will be compromised.
Apart from these reasons, it is best to follow the spark plug servicing time interval. Most spark plug manufacturers specify the life expectancy of the plugs. However, you should monitor the plugs yourself. Take them out of the engine and examine them thoroughly. If the spark plugs of your car appear burnt, chipped or corroded, it is time to replace them.
That said, if the spark plug in a car is just a little dirty, there’s nothing to worry about. The spark plug will get a bit rough and untidy after about 30,000 miles or so. If the spark plug appears to be glossy, the reason might be overheating. If the plug is overheated and has changed colour, you need to replace it.
Moreover, if you want to store your vehicle temporarily, you will need to remove the spark plugs to prevent them from rusting.
Where Can I Buy Spark Plugs From?
If you’re in search of quality plugs for your car in the UAE, take a look at the list of auto accessories and parts available on dubizzle. You will find spark plugs and many other car part and components at reasonable rates:
- Auto accessories and parts in Dubai
- Car spare parts for sale in Sharjah
- Auto parts for sale in Abu Dhabi
- Spare parts of cars in Ajman
FAQs
Do all vehicles require spark plugs?
Spark plugs are necessary for petrol cars. Diesel engines use compression and heat to induce combustion and do not require spark plugs. Electric vehicles also don’t need spark plugs as they are powered by batteries.
How many spark plugs does my car need?
This varies from engine to engine. A four-cylinder engine needs four spark plugs. A six-cylinder engine needs six spark plugs and so on.
Can I replace the spark plug of my car on my own?
Yes, just be sure you turn off the engine. Wait till it cools and disconnect the negative battery terminal before replacing the spark plugs.
What is the approximate cost of spark plug replacement in the UAE?
The cost of spark plug replacement depends on your car’s make and model, but it is generally around AED 75 to AED 180 for a regular car.
That is all you need to know about spark plugs in cars. To make sure your car runs smoothly, know the life expectancy of cars parts and replace them on time. If you intend to change your current vehicle or plan to buy another car, browse through a range of quality used cars available in Dubai.
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