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5 warning signs: when to change the spark plugs

Spark plugs… you’ve heard of them, haven’t you?

But we’re positive you’ve (also) heard about glow plugs, right? So this is the starting point to knowing the 5 signs that show when to change the spark plugs in your car.

Cars with combustion engines have something identical. They need fuel, air, and heat (or an ignition source) for their proper functioning. This ignition source comes from a spark plug.

The difference lies in the car’s engine type: gasoline engines use glow plugs, while diesel ones use spark plugs.

For now, learn a bit more about what these components are.

Man repairing an engine of a car

What are spark plugs? Why are they needed?

Spark plugs are a small component that helps start a car engine. While spark plugs create sparks as a heat source, they heat up.

When they reach a high temperature, the plugs begin to spark, hence the name.

How do spark plugs work?

To understand how these components work, we need to make the same comparison between the different plugs.

While glow plugs constantly work during the car’s functioning, spark plugs only work when starting the engine (which you should protect often). So it’s natural that you need to change them regularly.

When to change the spark plugs?

You don’t want to drive with burnt-out spark plugs, do you?

Then it’s best to pay close attention to these components. You should also check your car manufacturer’s manual. However, as a reference, you should replace spark plugs every 100,000 to 120,000 kilometers (in diesel cars) — though you should not replace them just based on this figure.

So be sure to ask your mechanic for advice while checking the manufacturer’s manual.

And now it’s time to know the 5 signs that show when to change the spark plugs.

When to change spark plugs: 5 signs to watch out for

You know your car better than anyone. So if you notice anything unusual, such as noises, the engine running differently, or fluid leaking from underneath the vehicle, these are clear signs that you should call your mechanic.

But you should also pay attention to the spark plugs because of their importance in starting your car.

Tools to repair cars in a garage

1. Start-up difficulties

This is when the car starts to hiccup and has trouble “starting” whenever you try it. It’s the main sign that something’s wrong because it shows the spark plugs’ wear.

2. Ongoing Failures

Are you driving and feeling the car jerking? That means the engine’s not working continuously, which shows that the spark plugs are worn and not burning the fuel as they should — causing those jolts.

3. Performance loss

Over time, and with wear on the spark plugs, the car’s response to throttle pressure is slower and takes longer to start.

4. Electrode corrosion

Some cheap fuel additives cause problems in spark plugs. Why? Because they’re corrosive.

In addition to this electrode corrosion, using cheap fuel accumulates residues that affect the flow of gases, which in turn clogs the car’s engine.

5. Electrode stains

Suppose you notice yellowish stains on the center electrode’s insulation. In that case, this shows that you use poor quality fuels — and that the fuel residues, instead of burning at high temperatures, stain the electrodes and affect their operation.

So don’t wait any longer to check that everything is in perfect working order in your car, ensuring it’s frequently maintained. This way, you avoid breakdowns or more severe problems.