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Spark Plugs and Wires: Is Replacing Them Worth It?
Are new spark plugs and wires worth the money? See what replacement can realistically improve, when it matters, and when it likely won't change much.
Routine Maintenance
Spark Plugs
5 guides, starting with Spark Plugs and Wires: Is Replacing Them Worth It?.
Bad Spark Plug Symptoms: What You'll Notice
Rough idle, misfires, hard starting and poor fuel economy can all point to worn spark plugs. See the common symptoms and how to tell what else it could be.
How Long Spark Plugs Last and When to Replace Them
Spark plug life ranges from about 20,000 to over 100,000 miles depending on type and engine. Learn what affects it and the signs it's time to replace them.
How to Choose the Right Spark Plugs for Your Car
Not sure which spark plugs to buy? Learn how to find the right ones for your engine, how copper, platinum and iridium differ, and which specs must match.
Spark Plug Heat Range Explained
Heat range describes how quickly a spark plug sheds heat, not how hot its spark is. Learn hot vs cold plugs, what the numbers mean and when to change them.
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