Will Bad Spark Plugs Cause a Car Not To Start?
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Yes, bad spark plugs can make a car not start! The engine won't be able to start if the spark plugs are unable to produce the spark needed to begin the combustion process.
Let’s discuss how faulty spark plugs can prevent your car from starting, what makes a spark plug go bad, and how to know that your spark plugs need changing.
Table of Contents
- What are Spark Plugs?
- Will Bad Spark Plugs Cause a Car Not To Start?
- What Causes a Spark Plug To Go Bad?
- How Do I Know My Spark Plugs Are Bad?
- When to Change Your Spark Plugs
- Best Car Deals by Category
What are Spark Plugs?
Most people don't think about the importance of their spark plugs, yet these tiny components play an essential role in the functioning of your vehicle.
For example, without proper working plugs, your car would not be able to run.
These tiny components are sometimes called the "small bolt of lightning."
When electricity flows through an electrical gap, it ignites the combustion chamber, which allows your car to start and remain powered up.
These durable and long-lasting plugs can withstand the high heat and pressure of your car's cylinders, and they can also burn off deposits that accumulated due to fuel additives.
Like other components in your vehicle, such as air filters and motor oil, spark plugs require regular maintenance and service to keep working correctly.
Most cars sold in the US require the replacement of these plugs every 30,000 to 50,000 miles.
Newer vehicles, such as SUVs, pickup trucks, and cars with advanced ignition systems do not require spark plug replacements.
However, there are still instances where a spark plug might fail.
On the other hand, a strong and healthy plug can help boost your car's fuel economy and keep running smoothly.
Will Bad Spark Plugs Cause a Car Not To Start?
Will bad spark plugs cause the car not to start? The answer is yes, a bad spark plug can prevent your car from starting.
If your vehicle doesn't start, it might result from a faulty spark plug.
This issue can cause the spark to sputter and stop working correctly, making it hard to ignite. It's essential to replace your spark plug immediately.
What Causes a Spark Plug To Go Bad?
Contrary to popular belief, quality spark plugs are not always the best way to improve the performance of your car. There are two types of plugs: iridium and platinum.
Although iridium is commonly used, costlier platinum-iridium is a better alternative.
Carbon fouling is arguably one of the most common reasons your spark plugs are bad.
When you remove the insulation from your wires, they can get exposed to various contaminants, including oil and dirt. They can also get dirty due to engine heat.
Another common issue with defective spark plugs is overheating.
If they get damaged too quickly, they can cause the wires to become misaligned, which can block the flow of electricity. Having bad plugs can also cause your vehicle to sputter.
How Do I Know My Spark Plugs Are Bad?
Your car will show signs that instantly tell you that the spark plugs are contaminated.
Some of these signs include;
1. Slow Acceleration
The prevalent cause of slow acceleration is a faulty ignition system.
Since modern cars have multiple sensors that determine when and how to fire the spark plug, the issue may be caused by a defective sensor. However, it's also possible that a worn-out spark plug causes the problem.
Spark plugs are components of an ignition system that work together to ignite the air-fuel mixture.
When the materials used to make these components wear out, their effectiveness decreases, which can result in a reduction in the vehicle's acceleration.
2. Engine Misfire
If the engine is misfiring, it's usually caused by an issue with the ignition system. In most cars, this issue is generally caused by a sensor malfunction.
However, it can also be caused by damaged wires or the tip of a spark plug.
When sputtering or stumbling sounds are heard from the engine, fuel economy and exhaust emissions may drop.
3. Poor Fuel Economy
When the spark plug works correctly, it can help boost the car's fuel economy.
However, if it's not working correctly, it can cause it to sputter or stop the engine.
One of the principal reasons why the plug is not working is because it's too close or too far apart.
Although it's usually recommended to replace the spark plug completely, it's also possible to adjust the plug.
For example, if your vehicle's fuel consumption increases, the issue may be caused by a worn-out spark plug.
4. Rough Idle
If a distinct and unsettling tone accompanies the rough idle sound, it might be caused by a faulty spark plug.
On the other hand, this issue could be caused by a cylinder firing while idle.
5. Engine Surging
If the engine suddenly surges and slows while accelerating, it might be caused by a faulty spark plug.
The issue could be caused by interrupting the car's internal combustion process.
The engine is sucking in too much air, which can cause the vehicle to sputter or stop.
6. Difficulty in Starting
Your vehicle's ignition system is composed of various components that must work together to function correctly.
If you have an issue starting your car, truck, or SUV, it could be a sign that the spark plugs are worn.
Having a professional mechanic inspect your vehicle's ignition system could help identify the cause of your issue.
Having the spark plugs regularly checked could extend the life of your vehicle's engine.
Spark plugs also wear out eventually, and replacing them could extend the life of your vehicle's engine.
When to Change Your Spark Plugs
Today, most car manufacturers will install extended-life spark plugs, usually rated for around 100,000 miles.
These are cheaper than standard plugs, and they sound great.
However, as these plugs approach their end of life, they start to widen, leading to reduced efficiency and the potential for misfiring.