How Long Do Spark Plugs Last? (+4 FAQs)

How long do spark plugs last?
And is there any way to make them last longer?

Luckily, yes, there is.
Proper maintenance and care can sufficiently extend the life of your new spark plugs and prevent problems with gas mileage and fuel economy — and that’s what we’ll discuss in this article.

This article will focus on spark plugs and how long they can last.
We’ll look at ways to make them last longer, including how to examine worn spark plugs, and go through some answers to frequently asked questions.

Let’s get started!

How Long Do Spark Plugs Last?

Spark plugs can last a very long time if maintained properly.

Most manufacturers recommend getting a spark plug replacement after every 30,000 miles (or more, for extended life spark plugs). This helps avoid decay, carbon fouling, or problems with worn spark plug tips. It also helps prevent issues with the cylinder or combustion chamber.

However, replacement needs also depend on the brand, model, and type of spark plugs you’re using.

Here’s a look at the lifetimes of different plug types:

A standard copper spark plug has an average life span of 10,000-20,000 miles.
Silver plugs, used for older vehicles, can last up to 20,000 miles.
Expensive iridium spark plugs or platinum spark plugs can last 60,000 miles.
Extended life spark plugs or long life spark plugs can last 100,000 miles.
High-end iridium spark plugs can last about 100,000 miles (although an extended life iridium spark plug may last up to 120,000 miles).
The double platinum spark plug is advertised to last up to 100,000 miles, but the actual mileage may vary from brand to brand.

Keeping this in mind, is there any way to make them last longer?

Can I Make Spark Plugs Last Longer?

Yes, you can!

As with most other engine parts, proper maintenance and care can prevent problems like vehicle engine misfire, a damaged spark plug, or carbon fouling. Routine maintenance also helps extend the life of your internal combustion engine.

Here are a few things you can do to maximize your spark plugs’ shelf life:

Pick the right spark plugs. When getting a new spark plug, stick to the ones recommended in your owner’s manual. Speak to a mechanic when upgrading to long life spark plugs if your manual doesn’t mention them.

Regularly inspect the electrode ends to ensure that they’re clean. Check to see that the center electrode and ground electrode do not have any rust buildup.

Ensure that your spark plug wire and porcelain insulators are coated in a dielectric compound. This prevents problems like premature corrosion and carbon deposits from penetrating the insulator.

Maintain the spark plug gap. If they’re too close, it may damage the old spark plug and cause engine misfire. And if too far, the plug may not generate an electric spark at all. It’s best to refer to your owner’s manual for the appropriate gap.

Regularly clean the mounting area. Accumulation of dust and dirt can sometimes misalign the spark plugs.

Most importantly, ensure that you have your mechanic take a look at any old spark plug within the recommended miles. A faulty spark plug or even damaged spark plug wiring can cause unnecessary problems to your engine.

Apart from these, make sure to get your new spark plugs examined and consider investing in extended life spark plugs.

And if you’re new to this, let your mechanic handle the maintenance and repairs. Incorrect handling of spark plugs can affect fuel consumption and internal combustion engine performance.

Now, here are some other things to know about vehicle spark plugs.

4 Spark Plug FAQs

Here are a few related spark plug queries and their answers:

1. How Can I Examine My Spark Plugs?

Checking your cylinder head on the internal combustion engine for a failing spark plug can be fairly simple (if you’re comfortable handling car parts).

Here’s how you do it:

Start by using a spark plug socket to remove the worn spark plugs.

For conventional spark plugs, you can use the spark plug socket to remove the spark plug.

For long life spark plugs, iridium spark plugs, or platinum ones, you may need a swivel spark plug socket to get them loose.

Examine the spark plug electrodes (center electrode and ground electrode) for black soot due to excess fuelair mixture. Check the spark plug gap and surrounding wires for any faults.

Replace worn spark plugs to avoid spark plug failure and problems like rough idling or the check engine light showing up.

Note: It’s best to consult your mechanic if you’re not confident about changing spark plugs yourself. A failing spark plug or wrong spark plug gap can cause a lot of engine damage.

2. What Happens If I Don’t Change My Spark Plugs?

Spark plugs deteriorate over time.

Your car may face loss of engine power, fuel efficiency, or problems with combustion. At some point, you risk spark plug failure, and your car simply won’t start.

As you drive, your spark plug gap opens up from damage and carbon fouling. This increases the voltage required by the ignition coil to generate an electrical spark. When the ignition coil encounters extreme voltage, there’s a chance of engine misfire issues.

The spark plug wire also becomes brittle over time. A bad spark plug wire can make the ignition coil lose contact with the ground electrode and the center electrode. You may end up with spark plug failure.

Other than that, you may also face some other issues if you don’t replace the worn spark plug. They include:

Decrease in fuel economy and fuel efficiency
Unresponsive ignition or failure with the ignition coil
Unstable, rough idling or stalling
Problems in the combustion chamber or engine failure

So, it’s best to keep changing spark plugs on a routine basis and keep an eye on their mileage.

3. What Are Some Signs That My Spark Plugs Are Failing?

Considering the various types of spark plugs in the market, it can become difficult to know when to change them.

Of course, you can track their mileage.
But what if you forget?

Here are some signs to look out for that indicate a faulty spark plug:

The check engine light is on
The vehicle has trouble starting and experiences rough idling
Reduced fuel economy and fuel efficiency, and increased fuel consumption
Formation of carbon deposits on the cylinder head
Failure in the ignition of the electric spark leads to misfires and engine noise

4. How Much Does It Cost To Replace Spark Plugs?

A new spark plug can cost anywhere between $16 to $100.
In addition to that, you can expect labor charges of somewhere around $40 to $150.

But why wonder how much it’ll cost when you can get an accurate cost estimate from the convenience of your home?

Enter AutoNation Mobile Service!

AutoNation Mobile Service is a mobile auto repair and maintenance solution with expert mechanics and convenient online booking. We offer a very reliable spark plug replacement service, and you can avail yourself of our 12-Month | 12,000 Miles warranty on all repairs.

Simply fill out this form for a spark plug replacement cost estimate!

Final Thoughts

A new spark plug can last for a long time.
And with routine maintenance, you don’t have to worry about dealing with a worn spark plug very often.

But in case of any issues, don’t forget to reach out to your mechanic.
Prompt spark plug inspection can save you a lot of money down the line. It will also prevent problems like carbon deposits, reduced gas mileage, or corrosion of your plugs.

So if you ever need help with a damaged spark plug, fuel change, or any vehicle problem, get hold of AutoNation Mobile Service.