How To Know If Spark Plug is Bad? 2021

This guide about, How to know if spark plug is bad has everything you need to know!

how to know if spark plug is bad

If you’re serious about your car, you NEED to maintain it for a long run.

Your car is not starting or missing that could be a mysterious, frustrating problem. And it’s a time to change your Spark Plug!

A spark plug is a critical component of a car that is the only thing to ignite the fuel in the combustion chamber. Plug works with an electrical signal which is sent from the ignition coil on a specific time to generate a spark.

The good spark plug is used to burn the fuel efficiently. A spark plug is the same as the fuel injector cleaner that requires routine service and maintenance to keep your car safe. It is directly linked to the engine performance so bad spark plug can create the problems of cold starting, misfiring during acceleration.

Your car requires electricity to operate most of your accessories, Spark plugs directly connected to the wires to conduct the ignition system and an alternator creates the electricity which transmitted through the spark plugs and generate the arcs of electricity.

Most auto mechanics suggest on average 30,000 to 50,000 miles you should replace your spark plugs. but it depends how are the type and condition.

So, How To Know If Spark Plug is Bad?

Here are 5 signs which need attention to check a spark plug.

  1. Difficulty starting the vehicle

At the first sign, If you car accelerating poorly it is a clear sign your spark plug is worn.

A plug emits the spark in a tiny gap which creates the ignition and your car start. Without a spark, your car won’t start.

  1. Your Car’s engine misfires

You already know an engine needs a spark to ignite and if the spark plugs are not working good so it can cause the cylinders to misfire.

  1. The harder-to-jump gap

The gap in a spark plug is the only source to provide the combustion at the right time. If the gap is too far apart, so the spark will not reach the right level and that would be ineffective.

  1. Poor fuel economy:

If the spark plug is not working or not providing a proper spark, you’ll see fuel will be wasted and a car will not receive the proper spark at the right can decrease your vehicle performance and high fuel consumption.

  1. Rough Idle

Idling is when your spark plugs are not working, the Car engine will create a rough and unusual noise, You can also feel the vibration in your car. Ignoring the problem can lead to constant knocking sound and rattling. It could damage the engine.


So NOW, comes to the conclusion your car is new or old the CARE of your car is very important.

Ensuring the maintenance of your auto oil and other critical engine components (spark plugs and wires) on a daily basis if they are working fine.

Look after your car every day it can help to increase the life of your car and save your money in the long run.

For the plugs, you can use high quality and extra high-performance spark plugs

We install Bosch spark plugs, and these are durable, efficient and can perform four times longer better and reliable.  

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