With all the variations in spark plugs out there—platinum-tipped, multi-electrode, split-electrode, iridium-based, and, of course, plain old copper—how’s a person supposed to know what kind of spark plugs to use in his or her BMW? Simple. Read the owner’s manual. Your BMW Spark Plugs, including the brand, model number, and correct gap, will be right there in black and white. Then you just visit your favorite online parts supplier and order your new BMW spark plugs.

Depending on what type of spark plugs are specified in your manual, you may or may not have to gap the plugs before installation. Read the instructions carefully to determine what gap, if any, your plugs need to be set at. And don’t use a plug socket to thread your new BMW spark plugs—at least not initially. Screw the spark plugs in by hand, or use a piece of vacuum line attached to the plug tower to get them started. Once they’re seated, you can finish tightening them with the socket. Following this procedure will prevent the BMW spark plugs from getting cross-threaded in your aluminum cylinder head.