Car Maintenance

What happens when spark plugs go bad

Spark plugs may be small, but they play a huge role in starting your car. The electrical spark they give off creates the ignition for the combustion needed to start your car. But what happens when spark plugs go bad?

Without a working spark plug you will have a hard time maintaining maximum power and will either misfire under acceleration or experience cold starts. Well, you wouldn’t want those things to happen, would you?

To do this, you need to know how often to replace your spark plugs.

About replacing spark plugs

Spark plugs generally do not need to be replaced frequently. In fact, your car can run for years and several miles before you have to worry about a replacement.

However, it is essential for certain car manufacturers to have a new spark plug installed every 30,000 miles. Note, however, that this is not a strict rule as a spark plug’s longevity depends on both its type and condition.

For example:

Copper connectors have the shortest lifespan. With that, you can expect to replace them more often.

Why you need to replace your spark plug

Spark plugs wear out with age. After being mistreated for hundreds or thousands of miles, you really can’t expect them to remain intact and perform excellently.

A good reason is deposits on the spark plugs, which lead to pre-ignition of the fuel. This leads to an unreliable power supply to your vehicle.

Another reason spark plugs can’t really last long is exposure to dirt, extreme temperatures, and the normal process of wear. These things increase the gap or space where the spark has to travel to create the right burn at the right time.

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The main benefit you get from replacing your spark plug is peace of mind. With a new one installed, you don’t have to worry about your car not starting.

In addition, purchasing new spark plugs also offers the following advantages:

  • Reduction of harmful emissions

    Regular engine tuning, especially when it comes to spark plugs, not only helps you save on fuel, but can also reduce air pollution.

  • Ensures smooth starts

    An old spark plug can cause your car to start jerkily. Replacing it with a new one provides smoother and more energetic starts.

  • Produces optimal combustion

    Having a fully functional spark plug means having an efficient and fully functional combustion system.

Signs that you need to replace your spark plug

What happens if spark plugs go bad?

Well, a lot of things can happen, and most of the time you won’t have a hard time recognizing the signs of a spark plug change.

Rattling and knocking noises are the first things you will notice. This typically happens when the spark plug starts to fail and combustion is no longer working properly.

Another sign is problems starting your car. You will feel like it is jerky and disjointed as the spark plug shows erratic performance.

Motor jumps can also occur. After making sudden jerks, the engine will start and then suddenly stop, preventing any vehicle movement.

Choosing the right spark plug type

One of the most common problems car owners face when changing spark plugs is knowing which spark plug will best suit their car.

Well, if you have the same problem, the simplest and most sensible answer is to check your car’s manual. The manufacturer knows best what your car’s engine needs and which spark plug can exactly meet those needs.

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In most cases you will see at least 4 different types of spark plugs. Below is a brief discussion of each type.

  • Copper spark plugs

    This type of spark plug has a solid copper core. However, its business end is typically a 2.5 mm diameter nickel alloy. This is the largest diameter electrode of the four.

    Consider this: if you have a smaller diameter, less voltage is required to produce the spark.

    Copper spark plugs are the best choice for older vehicles equipped with a low voltage distributor based ignition system. If your car has a DIS or distributorless ignition system or a COP (coil-on-plug) ignition system, you will find that this type wears out too quickly.

  • Individual platinum spark plugs

    Platinum spark plugs are ideal for newer vehicles with DIS. It is typically based on the copper spark plug with a platinum disc installed at the tip of its center electrode. Its material is harder than nickel, which means it can run hotter without fouling or scaling.

  • Double platinum spark plugs

    This type of spark plug has side electrodes that are not designed for back sparking. This means that if your car came with a double platinum spark plug, you can’t really downgrade to a single platinum spark plug or get a copper spark plug for your car.

    However, you can upgrade to a platinum combo connector or an iridium connector.

  • Iridium spark plugs

    While iridium is expensive, manufacturers of this type of spark plug reduce the diameter of their center electrode to around 0.4mm. Aside from reducing cost, the size of its center electrode also increases its firing efficiency.

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Knowing what happens when spark plugs go bad is important to knowing when to get a replacement. The signs are fairly obvious and you will recognize signs of a bad spark plug as soon as they appear. However, the tricky part is choosing the type of spark plug that suits your car’s needs. Because there are many options and factors to consider, don’t rush your decision.

An obvious solution is to check your car’s manufacturer and see what type they recommend. Some manufacturers are careful not to downgrade your existing spark plug as it can cause problems with your car and its engine. If you are unsure, you can always take your car to an experienced mechanic and get his opinion. This is the ideal course of action, especially if you are unsure how to install a spark plug as well.

Chloe Rimmer
Tv geek. Content practitioner. Creator. Wannabe beer nerd. Thinker. Passionate explorer. Proud bacon trailblazer. Travel fanatic. Award-winning introvert.

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