What Happens if You Don’t Change Your Spark Plugs?

What Happens if You Don't Change Your Spark Plugs

Unless you use an electric vehicle, you will need spark plugs in your vehicle. Every vehicle has an Internal Combustion Engine (ICE) in it.

The presence of a spark plug is needed for combustion to take place. If you have faulty spark plugs, your car will be unable to reach optimal performance and it will experience several engine issues.

Can Spark Plugs Become Faulty?

Yes, spark plugs can become faulty if it has been used for a very long time.

Spark plugs are really simple devices but they perform very important functions. The main function of a spark plug is to create a flash of lightning in the combustion chamber of the engine.

A spark plug transmits really high electrical energy in order for a spark to be created within the combustion chamber. The voltage from the spark plug can be as high as 20,000 to over 100,000 voltage.

What Can Make Spark Plugs Become Faulty?

Spark plugs can wear off in extreme temperatures, dust or dirt, or just normal wear and tear. Long use of spark plugs can cause them to become faulty. However, it is best to change the spark plugs immediately after they become faulty.

What Happens if You Don’t Change Your Spark Plugs?

Spark plugs ignite a mixture of fuel and air as it comes into the cylinder. It is that combustion of the mixture that powers the engine of a vehicle.

Spark plugs work in such a way that affects the overall engine performance so they need to be changed from time to time.

So, what happens if you don’t change your spark plugs?

1. Increase in Fuel Consumption

One of the noticeable things that will happen if you do not change your spark plugs is a reduced gas mileage. The wearing-out of spark plugs leads to a widening in the gap between electrodes. This can result in misfiring.

The mixture of oxygen and fuel will be injected into the combustion chamber and will leave without ignition. What this means is that your car will consume more fuel and produce less power.

To get enough torque, you will have to apply more pressure than normal on the gas pedal.

2. Unstable Idling

A faulty spark plug can result in unburned fuel. The combustion process takes place many times within a minute and so any time it misfires, an abrupt loss of power is created.

When the engine is left idle, this unstable firing of the cylinder will cause rough running of the engine. The engine will run but will be shaking and about to drop.

3. Engine Backfire

The backfiring of the engine takes place when the combustion of the oxygen-fuel mixture is created outside the combustion chambers. Sometimes, the backfiring may go into the intake valve, causing damage to some parts of the engine.

It is important for the mixture to occur at the right time and at the right place. When this is not done, the catalytic converter can get destroyed.

Replacing an overheated and bad catalytic converter is no joke, it is very expensive and you will have to spend a lot to get a new one. To avoid this, it is recommended that you change your spark plugs from time to time.

4. Knocking of the Engine

When fuel burns unevenly in the cylinder, the engine will knock. To avoid this, ignition has to occur at the right time in the combustion cycle.

If any of the oxygen and fuel mixture pockets ignite at the wrong time, a shock wave will be created that forms a pinging sound commonly known as knocking.

Knocking damages the pistons or cylinder walls because it comes with a lot of pressure inside the combustion chamber. Who wants his or her engine to knock? No one.

5. Slow Acceleration

Faulty spark plugs also affect the acceleration of a car. Faulty spark plugs cause misfiring and misfiring leads to gaps in the power production of the pistons. This lessens the rotational force on the crankshaft and reduced torque on the wheels.

6. Harmful Emissions

Damaged or bad spark plugs will get the catalytic converter damaged. That will result in excessive pollution. The combustion process in your car’s engine generates emissions (CO2) that are harmful to the environment.

These are a few of the problems that occur when you fail to change your spark plugs.

What to Do When Spark Plugs Becomes Faulty?

When your spark plugs get faulty, you should change them immediately. You can take your car to the automobile workshop for the mechanics to change it or you can DIY.

If you want to change your spark plugs yourself, follow these steps:

  • The ignition cables and coils should be removed
  • Look for damaged or faulty spark plugs and unscrew them. If you do not know which ones are faulty, just unscrew all of them and take a careful look at them
  • After marking the faulty spark plugs, replace them with new ones.
  • Apply oil on the threads of the spark plugs and screw them in place with the aid of a torque wrench.
  • Be sure that they are firmly in place with the use of a torque chart
  • Fix the ignition coils and cables back on the spark plugs.

Those are the steps to follow in changing a spark plug yourself. During the process, take extreme care to avoid dust or dirt getting into the cylinder. That could lead to more issues in the engine.

Also, you should not screw in the spark plugs too tightly, that might cause the thread of the cylinder head to get damaged. If that happens, you will need to replace the cylinder head entirely. It is an expensive repair.

Does Changing Spark Plugs Make a Difference?

Yes, changing spark plugs makes a difference because spark plugs play a major role in how your car drives.

If you change your spark plugs, you will not experience an increase in fuel consumption, unstable idling, slow acceleration, engine backfire, an engine knock, or harmful emissions caused by bad spark plugs.

I remember the day I wanted to go shopping with my car, as I put the car in reverse or gear, the car started shaking terribly.

I had to quickly drive it like that to an auto shop where it was discovered that it was just one faulty spark plug that caused the car to shake terribly.

How Long Should You Use a Spark Plug Before Changing it?

You should change your spark plugs according to what your car owner’s manual says. Most times, it is usually around 30,000 miles. This does not mean that if you notice the symptoms of a failing spark plug in your car, you should not change it till it gets to 30,000 miles.

If you notice abnormalities with your car’s engine, the first thing to come to your mind should be to check the spark plugs. You can use a car finder to locate the spark plugs in your car.

If they are dirty or corroded by gunk, that is a signal that there are carbon deposits there or possibly an oil leak even. When the auto man checked the plug, it was too corroded by deposits of an oil leak.

However, if your spark plugs look damaged, your engine will misfire or function at really high temperatures.

Many vehicle manufacturers have stated that spark plugs in cars should be replaced at intervals of 20,000 to 40,000 miles depending on how the vehicle is used and the model of the vehicle.

A high-performance car will need its spark plugs to be replaced more often such as a racing car.

What is the Cost of Replacing Spark Plugs?

You need to pay between $16 and $10 to get new spark plugs. You can replace the old spark plugs with the new ones yourself or get the help of a professional. If you need to use a professional’s help, you might be charged $40 to $150 for the cost of workmanship.

Final Thoughts

As you can see, spark plugs are really essential for the combustion process in your vehicle’s engine. Once they get faulty, the ignition and activation of your engine become difficult. You need to replace spark plugs in your car from time to time as instructed by the car owner’s manual.