- Written ByJohn Goreham
- 6/4/2024
Edited ByJulie Bausch Lent
Changing spark plugs was once a very commonly performed task when one would tune up a car. Today’s vehicles often run more than 100,000 miles before needing plugs changed mainly due to improvements in the technology and materials used in spark plugs.
Car Talk's Key Takeaway
It’s sensible to match the plugs you use with the brand of vehicle.Labor costs won’t break the bank on most models.Many high-quality plugs are simply private-labeled parts.Not a great area in which to try to save a few bucks.This can be a DIY project, however sometimes getting to the spark plugs can be challenging.
Top Recommendations
The following are recommendations based on interviews with ASE-certified mechanics.
- ACDelco: The go-to brand for GM vehicles.
- Motorcraft - The go-to brand for Ford and Lincoln branded vehicles.
- NGK (Niterra): A trusted aftermarket and OEM Brand for Toyota, Subaru, Mazda, and Honda vehicles. Also, a brand used for marine and off-road vehicles.
- OEM Spark Plugs: You won’t go wrong buying plugs from your vehicle’s parts counter.
- Hot rodders are switching to NGK. Some also use Champion on older vehicles.
What is a spark plug and what does it do?
The spark plugs in your engine provide the ignition source for the air-fuel mixture. Spark plugs are a modern miracle, doing their job a bazillion times, operating in incredibly hot and high-pressure conditions and they do this for decades in many cases. These days spark plugs may only need to be changed once or twice in a modern vehicle’s long life. Because they are relatively affordable for most vehicles and getting them in and out is a pain in the neck on many models, Car Talk recommends that our readers consider high-quality parts, rather than try to shave a few dollars off of this very important maintenance job.
What to consider when replacing spark plugs
Replacing spark plugs is a task that is now only done once or twice in most modern vehicles’ lifetime. Our ASE-certified mechanic suggests matching the plug brand with your model. Aftermarket plugs are available and they are often high in quality. Generally, they are less expensive than OEM plugs. The savings may be minimal compared to the total cost of maintenance for the vehicle. For this reason, we suggest considering OEM parts.
Your owner’s manual will have a schedule that suggests when to change your spark plugs. This can often be as long as 120,000 miles for many vehicles. Other vehicles have shorter lifespans for spark plugs. Unless your vehicle is displaying a check engine light or runs poorly, changing your plugs sooner than required has little or no benefit.
What costs are associated with replacing spark plugs
Spark plugs range in price from a high of around $50 to as low as around $10 per plug. On many cars, the cylinder count is the same as the plug count, but there are vehicles that have multiple spark plugs per cylinder. Your parts cost will be the cost of a plug times the number you need.
Mechanic Jr. Damato told us that the job can take from as little as 30 minutes to as many as three hours to change a set of spark plugs on a modern vehicle. Most of the labor is moving things to access the plugs. For example, Subaru favors “boxer” horizontally opposed engines. They sit in the engine bay and the plugs face the sides of the bay without room to get a tool in to remove and replace them. A service writer from a Subaru dealer told us, while we looked into the engine bay, that the process is either to drop the engine out or loosen its motor mounts and nudge it a bit using a lift and an engine jack so they can be accessed. That requires some training and some skill. On some models, changing the most hard-to-reach plugs is so difficult that some DIYers just change the ones that are practical to reach. Not our recommendation.
Read more on the Cost to Replace Your Spark Plugs here.
Car Talk expert ASE mechanics weigh in on spark plugs
Straight from our ASE-certified mechanics:
“On older vehicles, I will often use copper plugs rather than platinum or double platinum. I find they self-clean better.”
“I once visited a spark plug manufacturing plant and saw first-hand that many plugs are made identically and then labeled with different brands.”
“In our shop, we generally use the brand of plugs that are the same as the OEM’s. For example, ACDelco for GM, Motorcraft for Ford, NGK for Toyota, and so forth.”
-Jr. Damato, Junior’s Automotive Sales & Services
“Many tuners are using/recommending NGK plugs, especially for the Dodge Demon and Redeye versions of the Challenger Hellcat because they are just more reliable plugs than the stock ones.”
“I run Champion spark plugs in my classic MOPAR cars.”
-Patrick Rall, Stellpower
Can I DIY change my spark plugs?
Changing spark plugs is not technically challenging, but it can be a tricky process on some vehicles with hard-to-access plugs. Also, if the plugs have been in longer than they were meant to be, they may be reluctant to come out. Stripping the socket into which one is threaded is never easy to resolve and requires skills and special tools. It is also important to ensure debris does not drop into the plug’s space. Finally, installing plugs requires they be properly gapped. Factory plugs may be preset to the right gap, but it’s important to make sure this is the case.
On a scale of one to five where one is changing a car’s oil and a filter and five is a valve job, changing plugs is a 2.
Conclusion
Spark plugs generally cost around $100 a set, and labor to have them changed by a qualified mechanic typically ranges from 30 minutes to about three hours of shop time. Changing spark plugs is not an expensive service and is not done routinely but only rarely in modern vehicles. Our expert mechanic suggests choosing your plugs from the OEM, or from the brand that manufactures the OEM plugs for your vehicle. ACDelco, Motorcraft, and NGK are top brands for spark plugs.
Who are Car Talk’s certified experts?
Our Car Talk staffers live the car life and have many special skills, but none of us are experts in all areas of car ownership. For our vehicle maintenance and repair focus stories, we interview ASE-certified mechanics who perform car repairs and have a long history of doing so. They know how to do these repairs at a very detailed level, and they know what products and brands work and can be trusted and which to avoid.
For this story, Junior Damato, owner and operator of Junior’s Automotive Sales and Service in Middleboro, Mass. served as our primary go-to expert. Junior is a long-time Car Talk associate whose relationship with Ray and Bugsy spans many decades. He began his professional career in trade school and upon graduation went on to serve in the U.S. military as an engine specialist. After completing his service, he began working as a mechanic and earned his ASE Certification. Junior also hosted a radio program of his own. Junior Damato is a long-time New England Motor Press Member.
Car Talk was also helped by Patrick Rall. Patrick is an expert on the subject of drag racing and Dodge SRT performance vehicles. He owns a racecar as well as a Challenger Hellcat used as his daily driver along with multiple other Dodge and Ram vehicles. Patrick is a daily contributor to Stellpower.
Read more on the topic of Car Owning here.
FAQ
- Which car park plug is best for my car?
Car Talk’s experts recommend matching the brand of spark plug to your car. For example, ACDelco for GM and Motorcraft for Ford. NGK is also a go-brand for many enthusiasts.
- Do expensive spark plugs make a difference?
If your vehicle is not running poorly or sending you error codes, changing your plugs sooner than necessary is unlikely to make any positive change in how your car runs. When you do change plugs, sticking with the OEM brand is often a good choice.
- Do fancy spark plugs help older cars?
Car Talk’s expert mechanic, Jr. Damato advises that less expensive copper plugs are often better than fancy plugs for older cars.
- How do I know if I need to change my spark plugs?
Your owner's manual will have a change interval. If you are having engine trouble, it’s best to get a mechanic’s diagnosis before changing parts.
Editor's note and disclaimer: Car Talk is supported by our fans, readers and listeners. When you click on some of the links on our website, we may receive referral compensation. However, you should know that the recommendations we make are based on our independent editorial review and analyses.
