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How To Tell If Your Car Has a Bad Spark Plug? 7 Symptoms

How To Tell If Your Car Has a Bad Spark Plug? 7 Symptoms

Are you interested in “how to tell if your car has a bad spark plug?” Look for these 7 symptoms:

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  1. Engine misfiring
  2. Reduced fuel economy
  3. Engine backfiring
  4. Engine knocking
  5. Loss of acceleration
  6. Rough idling
  7. Difficulty starting

The spark plug is a minor element in your vehicle's combustion system, but it has a very important role. It provides the necessary spark to ignite the air-fuel mixture in the cylinders causing your engine to produce energy.

With a failing spark plug, you cannot generate any energy, which means you might get to a point where you can't drive your vehicle. In addition, the spark plug is not designed to last forever, and there will be a point of time where you must replace it based on what is specified in your vehicle's owner’s manual.

However, there are instances where the spark plug might fail prematurely, which means you have to monitor for any symptoms indicating that the spark plug is failing. The good news is that these symptoms are known, and many automotive experts put together a list of comments in terms of a bad spark plug.

This article provides you with all you need to know to answer “how to tell if your car has a bad spark plug?” It will also provide additional details to help you resolve the problem and replace your spark plug immediately.


Signs of Bad Spark Plugs

What is the spark plug, and what does it do?

Before we highlight the details about “how to tell if your car has a bad spark plug?” We must get a general understanding of the main role of the spark plug in your Combustion system.

The spark plug is part of the different elements that work together to generate the energy in your cylinders. For the cylinders to produce the right amount of energy at the right time, they'll need a specific amount of fuel, air, and the right spark at the right time. If any of these elements were not provided at the right time, your vehicle would deal with what's known as the vehicle engine misfire.

Therefore, having a bad spark plug is one of those critical situations you might deal with. However, since you have multiple spark plugs depending on the number of cylinders, you might not necessarily deal with a completely shutting down vehicle when one spark plug goes bad. However, things get extremely complicated if all the spark plugs go bad together, which is not surprising because they typically have the same lifespan.

How long does the spark plug last?

The spark plug is a relatively endurable component in your vehicle. It is expected to go bad between 10,000 and 20,000 miles. However, this time range differs significantly depending on your spark plug type.

Or example, if you're using one of those high-quality spark plugs, I expect the lifespan of the spark look to be much longer. However, if you just went with the standard regular type of spark plugs, that's when you might deal with sparkplug complications at the early stages of your vehicle’s lifespan.

Spark Plug Replacement Price

How to tell if your car has a bad spark plug?

Since the spark plug is a very sensitive component in your engine, and without it, you might deal with significant issues that could get you to a point where you can't drive your car, you must understand when the spark plug goes bad.

As you mentioned earlier, there is a specific expected lifespan for the spark plug, but at some point in time or because of various reasons, you can deal with a damaged spark plug prematurely. That's why it is critical for you as a driver to familiarize yourself with the different symptoms indicating you're dealing with a bad spark plug.

Thus, if you're wondering, “how to tell if your car Has a bad spark plug?” Monitor these symptoms:

1.    Engine misfiring

As we mentioned before, the spark plug plays a significant role in your vehicle's engine function. When there is no spark at the right time, you'll deal with engine misfiring because of this missed component.

Insert instance, your engine's firing might lead to a check engine light illuminating. That's why it's critical, but you do not take the issue easy because it might be related to a significant problem.

Keep in mind that the check engine light is related to various issues that could be facing your vehicle. Therefore, you cannot immediately say that you're dealing with an engine misfiring unless your mechanic performs a thorough inspection and confirms.

Therefore, whenever you notice the engine misfiring in the form of a check engine light illuminating on the dashboard, you must consult your mechanic immediately and let him know that you're dealing with this. The good thing is that you will also notice other symptoms simultaneously, which could narrow down your potential list of culprits and help you identify whether you're dealing with a bad spark plug.

2.    Reduced fuel economy

Your engine is designed in a precise way. It expects a specific amount of fuel, air, and accurate timing for the spark plug. If the spark plug was not produced correctly, your engine might not fully burn and explode the air-fuel mixture on time. As a result, you'll notice that your car will consume more fuel than before. As a result, you'll see that you need to visit the gas station more than before.

Note that the reduction in fuel economy might be related to other symptoms and other issues, so you cannot immediately say it's a problem with this work look unless your mechanic performs the full inspection.

3.    Engine backfiring

Another thing you might deal with is if you're having a bad issue with a spark plug. Engine backfiring is an extremely weird situation. Many inexperienced drivers might panic because of it, and that's why you want to prevent it as much as possible by monitoring your spark plugs.

Spark Plug Non Fouler

4.    Engine knocking

Engine knocking is another expected symptom for Yvette spark plugs, and you'll notice that this knocking will be much louder if you have multiple spark plugs failing simultaneously. Remember that engine locking might also be related to your vehicle type, especially if you're driving an older car.

Also, you might experience engine knocking when you're driving a vehicle that is expecting a premium fuel, and you decided to go with that low-quality octane level fuel here; therefore, check that you did not mess up the fuel choice first before suspecting it's an issue with a bad spark plug.

5.    Loss of acceleration

Unsurprisingly, when you're dealing with a low fuel economy and when the spark is not provided on time, you notice that your vehicle is not accelerating as it should. You notice this more when you drive at the highway speed and when driving on city roads.

Loss of acceleration can be extremely dangerous if you're driving in traffic or driving at highway speed and everybody is speeding. Imagine what could happen when your vehicle stops accelerating suddenly without any previous warning signs to its surrounding drivers?! That could lead to a catastrophic situation.

6.    Rough idling

Rough idling is also another symptom of a bad spark plug. Typically, your vehicle should not make weird loud noises when you're idle. However, if you started to notice that it's acting a little bit weird and the idling processes a little bit rough, that's when you might suspect the scribe blog. Remember that rough idling is another related symptom to other problems like the mentioned symptoms. You must confirm whether you're dealing with a bad spark block or something else with your mechanic.

7.    Difficulty starting

Finally, come if the spark plugs go bad all those same times, you might not be able to start your vehicle at all. So there are some instances where most of the spark plugs might go bad. That's when you notice that it's hard to start your car, and it might start at this time, but the other time it might not.

Difficulty starting is one of those problems made with a long list of potential culprits.

how often should you change spark plugs
how often should you change spark plugs

How much does it cost to fix a bad spark plug?

Replacing the spark plug is not a very expensive job. It typically costs you between $196 and $251, including labor and parts costs. However, keep in mind that if you have the right mechanical skill sets and can replace the spark plug yourself, you can eliminate the labor cost.

However, since the spark plug is a component within your engine, you mustn't attempt to replace them unless you have the skills. In other words, if you do better placement wrong, it can introduce some other problems that will cost you more money down the road than going to the mechanic to replace the spark plugs.

What are the different types of spark plugs?

Since these spark plugs have a specific lifespan, you must understand that there are some higher-quality spark plugs where you don't have to worry about replacing them very often.

There are many good options in the market for different spark plugs to consider in your next replacement, allowing you to buy more time and not worry about the spark plugs for extended times. First, however, you must consult your mechanic or check with your vehicle’s owner’s manual to confirm whether your car is compatible with the different types of sparks plugs or not.

Here are the different types of sparks plugs in the world of automobiles:

  • Copper spark plugs
  • Platinum spark plugs
  • Iridium spark wants
  • Pulstar spark plugs

Depending on the quality of the spark plug, prices can climb significantly. Therefore, before deciding between switching to a higher quality spark plug, consider evaluating your budget and checking the main pros and cons of it stretching to these spark plugs. If you found that the benefits you'll get are not as good as the amount of money you're going to pay extra for the higher quality spark plug, that's when you have to consider a little bit lower quality spark plug.

What Does A Spark Plug Misfire Feel Like

Final thoughts

The spark plugs are critical components in your vehicle because they provide the required spark to ignite your air-fuel mixture. When the spark plugs go bad, you'll deal with many symptoms, and this article provided you with a summary of the seven most common symptoms of a bad spark plug.

Once you understand these symptoms, you'll be able to answer the question, “how to tell if your car has a bad spark plug?” Once you confirm that the issue is coming from the bad spark plug, you'll have to replace it immediately.

If you got to the point where you had to deal with significant problems following a bad spark, well, that's not the end of the world because you can always sell your vehicle and take advantage of its value to buy a better car here if you're looking for someone to buy your vehicle. If you're struggling because of its complicated problems, cash cars buyer is always here to help you!

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