Updated at: 05-03-2022 - By: micdot

Because they have such a significant impact on the vehicle’s overall performance and condition, spark plug changes should be performed on a regular basis. In spite of the fact that many customers have already replaced their spark plugs, they are still having some issues. So, let’s speak about how to change your spark plugs and some of the issues you can run into after doing so. An important part of your engine is the spark plug. The source of the spark is responsible for igniting the gas or air combination. As a result, your engine will generate power as a result of the ignition spark being supplied.

The two wires connected to these plugs are forming an electric arc. Both of these leads are not touching, but they are close enough that the electricity can pass through the gap. Your ignition system relies heavily on the performance of your spark plug. Keeping an eye on them and replacing them as needed is essential. Continue reading if you’d want to learn more.

What Problems Can You Experience After Changing Spark Plugs?

Spark plugs are frequently replaced by drivers who notice minor issues with their vehicle’s condition and performance. However, some users are still experiencing issues even after replacing the spark plugs. After changing your spark plugs, here are some of the issues you may encounter.

Hard Start

Some motorists have reported difficulty starting their vehicles after removing and replacing their spark plugs. This could be the result of a malfunctioning spark plug.

Engine Noise

You may hear rattling or knocking noises after changing your spark plugs. A misfiring spark plug will make these noises. Combustion problems, such as faulty pistons, will be the cause of this leakage.

Misfiring spark plugs cause these noises because pistons need high velocity to travel. A defective spark plug may be the blame for these issues..

Poor Fuel Economy

Perhaps you’ve noticed that your fuel efficiency isn’t getting any better? Good fuel economy is mostly due to the spark plugs of a vehicle. If you’ve changed your spark plugs, you’ve probably noticed an increase in your vehicle’s fuel economy.

Reduction In Performance

After changing your spark plugs, you may observe that your vehicle’s performance has not been affected. Your engine’s performance will suffer if your spark plugs aren’t operating properly while you accelerate or shift gears.

Problems after changing spark plugs + Engine Misfires + Car Misfires + spark plugs

Why Does My Car Shake After I Changed The Spark Plugs?

Spark plugs have been blamed for causing a shaky ride for certain customers. Your vehicle’s trembling can be caused by a variety of factors. For instance, if you have low fuel pressures or misfires, this could be a problem.

But if you’ve just changed your spark plugs and wish to remain with the spark plugs, you might have faulty spark plugs. Idle air control valve failure is another possibility. As a result, your engine may idle below normal.

Can New Spark Plugs Cause Rough Idle?

New spark plugs can generate an irregular idle, but it is quite rare for them to do so. We’re talking about a brand-new spark plug here. Your automobile may be idling erratically for a variety of reasons.

There is a chance, though, that your spark plugs have failed or are defective. It’s probably preferable to have it checked by a professional. Changing your spark plugs incorrectly may be to blame.

What Should I Check After Changing Spark Plugs?

If your engine is idling rough, you should investigate more. Your idling should be smooth if your spark plug is fresh. Make sure your automobile will start without a hitch. You shouldn’t have any more issues starting your automobile now that you have a new spark plug. While you’re at it, you should also inspect your engine for any misfires. An engine misfire can be caused by a defective spark plug.

As a result, you must ensure that the new spark plugs you purchased are not defective. You should also inspect your engine to see if it is surging. Additionally, keep tabs on how much gas you’re putting in. Spark plugs must be replaced if you are experiencing poor fuel economy. There must be a problem with your spark plugs or other parts of your car if you’ve replaced them and your fuel usage is still excessive. Also check if your car’s acceleration is slow.

Should I Reset ECU After Changing Spark Plugs?

After changing their spark plugs, several folks are wondering if they should reset their ECU. Some experts advise against resetting your ECU. In some cases, it is also claimed that you do not need to reset your ECU after changing your spark plugs.

A reset of the ECU may be a good idea for some, but others will argue that there are no advantages to doing so. While it’s possible to reset your ECU, it’s important to know if your vehicle is due for an inspection before doing so.

Can Spark Plugs Change Cause A Car Not To Start?

Yes, faulty spark plugs are at blame if your vehicle won’t start. Many users have reported that after changing their spark plugs, their cars would not start. Coils and plugs are the root cause of this problem.

Changed Spark Plugs Now Car Won’t Start: What To Do?

Check to see if there are any plug wires running directly from the coil or distributor and down into the spark plugs if they are fastened firmly and correctly if your car won’t start. You can also run a diagnostic and receive a visual representation of the results. See how your car’s wiring are connected to each other in a picture. There is a chance that you have connected the cables incorrectly.


The most crucial thing you can do for your car is to replace your spark plugs. For this reason, it is important to keep your vehicle’s spark plugs in good condition.

Some people, on the other hand, are still experiencing issues even after switching out their spark plugs. To be safe, make sure your new spark plugs are checked. Keep an eye out for any flaws or damage.