How often do spark plugs need changing

While your engine runs on gasoline, it also requires electricity. It’s needed to operate most of your accessories, but is also required to make the engine run. Spark plugs connect to wires that lead to the ignition system....

While your engine runs on gasoline, it also requires electricity. It’s needed to operate most of your accessories, but is also required to make the engine run. Spark plugs connect to wires that lead to the ignition system. Electricity is created by the alternator and sent to the plugs, which create arcs of electricity. This is what ignites the fuel in your engine’s cylinders, creating the combustion that pushes the pistons down and actually turns the engine. Spark plugs are vital parts of your car.

Spark plug wear

Like most other components of your engine, spark plugs wear down over time. The primary type of wear here is with the electrode. If you look at a spark plug, you’ll notice one end is narrow and tapered – this is where the wire connects to it. The other end is bulbous, with a small metal rod coming out of the center, and a metal hook to one side. That center rod is the electrode – electricity arcs from that to the hook.

Through normal use, the electrode on each spark plug does wear down. Eventually, it becomes so worn that it doesn’t create as much (or any) electric arc, which has a direct and immediate effect on your engine operation.

When to replace spark plugs

If you check your owner’s manual, you’ll probably find that your automaker recommends you replace your spark plugs roughly every 30,000 miles. That’s fine if you’re using stock spark plugs. However, the actual timing of replacement will vary depending on other factors.

  • High Performance: If you have high performance spark plugs, it’s possible that you will need to replace them more often, as the electrode can wear down faster.

  • Long Life: Some spark plugs are made to have a longer life. Their electrodes do not wear down as quickly, meaning that you won’t need to replace them as frequently. Look for plugs made from iridium or platinum for the longest life (copper has the shortest lifespan – generally about 20,000 miles).

  • Oil Leaks: When you pull a spark plug out of the engine, the base should be relatively clean. If there is oil present, it means there’s a leak. Not only does that mean you’ll need to replace a blown seal, but it means your spark plugs will need to be changed more frequently because of contamination.

  • High Revs: If you regularly “put your car through its paces,” you’ll put additional wear and tear on your spark plugs, meaning that you’ll need to replace them more often. Drivers with a lighter foot will enjoy longer life from their plugs.

If your engine seems to be running rough, or skipping, chances are good that it’s time to have your plugs replaced. Other symptoms can include rough idling and stalling.



The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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Pardeep

21 years of experience

1068 reviews

Pardeep

21 years of experience

Jeep Cherokee V6-3.2L - Spark Plugs - Cupertino, California

Great service. Looking forward to build a good relationship different from the usual mechanics that is always trying to charge you more. Pradeep made me the impression that he is different. Cool.

Toyota Prius - Spark Plugs - Fremont, California

Mr. Singh was on time, gave good advice and did the services very well. By the way, this is the third time I have my car serviced by him.

Keven

7 years of experience

118 reviews

Keven

7 years of experience

Kia Soul L4-2.0L - Spark Plugs - Puyallup, Washington

Kevin, is wonderful. He is on time and very efficient. He explains things very well and answered all my questions. Very friendly too. I would highly recommend Keven and plan on using him again if mechanic service is needed.

Toyota Sienna - Spark Plugs - Spanaway, Washington

He was very efficient, very knowledgeable and very sweet. Thank you for your time and your patience with my vehicle.

Claud

8 years of experience

475 reviews

Claud

8 years of experience

Dodge Durango V8-4.7L - Spark Plugs - Detroit, Michigan

On time, very knowledgeable, and professional. Excellent job, thank you. Will call for service again.

Ford Flex - Spark Plugs - Rochester, Michigan

Claud did a great work for a big job on my car. Brought it back from the dead. Will definitely be booking him in the future.

Rodney

36 years of experience

541 reviews

Rodney

36 years of experience

Volkswagen CC L4-2.0L Turbo - Spark Plugs - Sacramento, California

Awesome mechanic worked really fast and help me understand a lot more about my car honestly I didn’t know much and he was really helpful and definitely will be booking with him again

Jeep Cherokee - Spark Plugs - Elk Grove, California

I’m so pleased with Rodney, he’s very thorough. This is my third time using Rodney (Your Mechanic). I have no complaints. I appreciate him repairing my vehicle.

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How do I know if my spark plugs need changing?

7 Signs You Need to Replace Your Spark Plugs.
The car is hard to start. ... .
The engine misfires. ... .
You're heading to the gas station more often. ... .
The engine idling is rough and noisy. ... .
Your car struggles to accelerate. ... .
The engine is really loud during normal driving. ... .
Your 'check engine' light is on..

How long should a set of spark plugs last?

How long spark plugs last varies by manufacturer and vehicle, but on many vehicles today, they should be good for 100,000 or more miles. Some vehicles, though, will have shorter intervals, particularly performance and luxury models.

What happens if you don't change your spark plugs?

If you let your spark plugs go for too long, you could do some severe damage to your engine. The deposits that build upon the plugs can eventually cause them to misfire. When this happens, the unburned fuel in the cylinders can start to eat away at the cylinder walls.