For a four-cylinder engine, you’ll need four spark plugs. At least, that’s the norm—one spark plug for each cylinder head.

While certain engines may employ twin spark heads to ignite engine charge, it’s fairly uncommon—at least for the average passenger vehicle.

If you’re unsure of your car’s engine specs, you can always check your owner’s manual for details regarding your specific model. Your car’s manual should also contain an overview of a basic car maintenance routine you should be following for your vehicle—which will include information on how to care for (and when to replace) your spark plugs.

If you’re looking for new spark plugs, stores like Advanced Auto Parts typically have affordable aftermarket products, and can even help you find the right parts to buy for your vehicle.

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