What happens when spark plugs go bad?

Is your car’s engine not performing well and showing unusual issues? Then your first duty will be to check the spark plug because most of the engine issues arise from a bad spark plug. We are about to elaborately say, what are the possible outcomes of bad spark plugs.

You will also know about the reasons and precautions regarding spark plugs going bad. Hope your vehicle is going to benefit from it! 


1. Lack of maintenance:

 When one does car servicing, most of the time, the spark plugs are overlooked! But they require maintenance to be the most crucial component in there. As a result, oil from the engine starts to build up in the plugs’ combustion chambers.

Over time, the oil congests the chambers resulting in improper functioning. Hence, if the chambers are cleaned once a while, then the spark plugs won’t go bad.

2. Overheating:

 The spark plug can get overheated due to lots of reasons. One of the main reasons is when your engine gets overheated and the cooling system malfunctions, which passes on the heat to the spark plugs.

Especially, the tip of the spark plug gets affected first due to overheating and causes premature wearing.

3. Carbon build-up:

 Like oil, you need to see if your spark plugs are getting carbon build-up or not. The longtime build-up from carbon deposits makes the spark plugs look black and corroded.

Carbon can damage the spark plugs through dirty fuel injectors, clogged air filter, or even cracked distributor cases. 

4. Improper placement: 

Improper placement of the spark plugs, such as gaps, causes the insulator tip to stress, making the plugs erode out faster. If any one’s gapping is misplaced, then slowly, the entire spark plug set suffers.


1. Hampered acceleration:

 Acceleration will get rough or slowed down due to a bad spark plug. The spark plugs’ air-fuel combustion chambers won’t ignite as much as they should create a smooth and steady acceleration.

2. Engine idling:

 It’s the most common problem everyone faces that occur due to bad spark plug misfiring. The fuel does not burn enough fuel because of worn-out plugs.

Hence, your car starts rough idling. In some cases, the car also starts to sound like a tractor.

3. Fast fuel consumption:

Bad Spark plugs handle fuel inefficiently. Hence, you will have to visit the gas station often, as more gas gets consumed in less time.

If your car is old, you may not find fast-gas consumption relatable with bad spark plugs. Instead, you would think the engine got faulty over time.  Still, do check the spark plugs too.

4. Engine light showing misfire:

 Often, engine control displays misfiring, which occurs for bad spark plugs. Therefore, the trouble code on display brightens up. Then you know that something is wrong with the spark plugs.


Check them:

 Even if you do nothing for them, you should check them at least after every 24 hours of use. If any issue arises, you will get to beforehand rather than being late to prevent the mishaps.

Clean them:

 As a part of maintenance, clean the spark plugs once a while. Routine Cleaning will elongate their shelf life and prevent them from getting any buildup. Make sure you know the cleaning process and do not use harsh cleaners.

Hire a professional for any replacement: 

If you think of saving labor cost by replacing the spark plugs yourself with no prior knowledge, you are thinking wrong. Not placing the spark plugs the right way and position troubleshoot their performance to a great extent.

Spark Plug Location:

Spark plugs are placed under the ignition coil of the engine’s cylinder. Mostly, they are under the engine’s top cover. However, in some vehicles, the plugs are situated beside the cylinder head that makes the placement a bit harder.



Why is Spark Plug important in a vehicle?

The engine makes your vehicle run, and spark plugs make that engine run! So, now you know why it is such an essential component in a vehicle. These plugs are the engine’s power producers.

Does every vehicle contain spark plugs?

Any vehicle that runs with an engine contains a spark plug! Without them, the engine won’t produce fuel by converting chemical energy.


Now that you the results of spark plug going bad and its importance for your vehicle keep them safe! If you ever feel the need to change the spark plugs, then do that without any hesitation, as their cost is insignificant compared to the entire vehicle.

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