Top 6 Signs That Your Spark Plugs Need Replacement

Do you know the signs to look for when your spark plugs need replacement?

Spark plug trouble is one of the most easily detectable car issues.

However, most drivers still have a hard time figuring it out.

So much so that most will end up experiencing signs and warnings and still end up not doing anything about it.

This should never be the case.

Responsible driving is not limited to road activities.

It also entails conscious learning and general awareness of all possible car issues.

This post will help you become a better and more responsible driver as it will enlist signs that will make it easier for you to determine if your spark plugs need replacement.

Expert and experienced drivers will also benefit from remembering and taking note of the following signs as they may have already forgotten some.

But first, what are spark plugs?

Spark plugs are supremely important.

They serve as the very instrument that delivers electricity from your car’s ignition system to its combustion chamber.

They supply the necessary electrical spark that triggers the mixture of air and fuel that allows for your engine to run.

Your car will basically not run if your spark plugs are not in good condition. It’s a good thing that before that even happens, your car will go out of its way to warn you.

This post will enlist all the possible signs and warnings that your car will show and manifest to tell you that you need to have your spark plugs checked and duly replaced. 

Top 6 Signs That Tell You That You Need To Have Your Spark Plugs Replaced 

Sign #1: You experience engine misfires.

Since spark plugs are essential in starting your engine, you will definitely experience engine misfires if they are already in bad condition.

This is the most common sign that your spark plugs need to be checked already. When you experience engine misfires, your engine will run rough at idle.

You will also have a hard time accelerating. 

This is very easy to detect as you will feel the engine yourself.

They will not run and sound the way they used to. You will also notice sudden changes in your fuel economy.

Sign #2: Your engine light sends warning signals.

Cars are now smarter. So much so that they can now easily guide clueless drivers if there are foreseen troubles through their warning lights.

The more advanced your car is, the more complicated its warning light system will be. 

When an engine misfires, your car’s control unit will automatically be alerted.

Upon alert, it will go out of its way to determine the cause of the misfire. Upon determination, your car’s control unit will send a trouble code.

Such trouble code is what you’d see when your car’s warning lights blink or light up. Hence, you should be very familiar with your car’s warning lights.

Here at The Automotive Men, we will never stop advising our readers to always keep their car’s manual at hand.

It’s best to always keep it by the driver’s side as cars have different warning light mechanisms and symbols.

It will also be best if you memorize or read your car manual’s warning light guide every now and then for better familiarity.

Good familiarity will always be beneficial as it will be easier for you to know if your car is telling you that it is sensing a problem.

Sign #3: You will experience rough idle.

You experience rough idle when your spark plugs are in bad condition.

When bad spark plugs cause an engine misfire, your car’s O2 sensors may be tricked by the presence of unburned fuel.

Your car’s O2 sensor will immediately act on it and opt to regulate. Upon your O2 sensor’s fuel regulation, your fuel mixture will turn out lean.

This causes rough idle and sets up more misfires on cylinders.

Sign #4: You will experience rough or slow acceleration.

Because of your car’s confused O2 sensor, you will also have a hard time accelerating.

Take note if you’ve been having a hard time accelerating as it surely is an instance that calls for you to have your spark plugs checked already.

Sign #5:You have a hard time starting your engine.

Starting an engine requires good solid electric sparks.

When your spark plugs are in a bad condition, they will not be able to deliver such. Hence, you will have a hard time starting your engine.

So much so that your engines might not even start at all. Long cranking time is also a sign that your spark plugs need to be checked already. 

Sign #6: You will experience poor fuel economy.

A messed up O2 sensor influenced by poorly performing spark plus will greatly affect your fuel economy.

This is because misfires greatly affect the state, wellness, and effectivity of your fuel mixture.

Make it a point to be observant when it comes to your car’s unique fuel economy.

The more sensitive you are to its changes, the easier it will be for you to detect if your spark plugs or any part of your engine is experiencing difficulties.

Being highly sensitive to the needs of your cars will definitely reap you numerous rewards and savings. 

Will a bad spark plug damage my engine?

It will not damage your engine immediately but it will at some point.

So yes, your engine will ultimately end up being damaged. To prevent this, do take note of the following signs.

Once you experience them, make it a point to deal with the situation the soonest time possible.

The sooner, the better.

Your spark plugs are highly important and you should always make it a point to prioritize their optimum performance. 


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