9 Tools to Remove Spark Plugs

What to Know About Changing a Spark Plug

Changing spark plugs is basic DIY car maintenance that can save you hundreds of dollars in labor. A new set of spark plugs can improve engine performance and fuel economy while lowering emission levels. Spark plug removal tools make installing new spark plugs easier, especially when the plugs are in hard-to-reach areas.

Before purchasing spark plug removal tools, check your owner’s manual or local parts store to learn what size spark plugs and the kind of ignition system your car has.

Coil Over Plug ignition systems do not use spark plug wires. On some V-6 engines the intake manifold may have to be removed to replace the spark plugs. Leave that to a pro. However, if you can access the rear cylinder head, with the right tools you can do this job yourself.

These are the tools you’ll need to replace your spark plugs. All sockets and ratchets listed are 3/8-in. drive:

• Spark plug gap gauge: Correctly sets the “gap” between a spark plug’s side and center electrodes to the manufacturer’s specifications.
• Needle-nose spark plug pliers: Removes spark plug wire boots in tight places. Pliers with serrated jaws lessen the chance of damaging a spark plug wire.
• Spark plug wire pliers/pullers: Remove hard-to-reach spark plug wires while providing more protection for the wire boot. These pliers come in two designs, straight or offset (angled). Look for sturdy jaws and handles that are insulated and won’t twist.
• Spark plug sockets: These feature a rubber boot or magnet to hold a spark plug in place while removing or installing. They also protect the porcelain insulator. Spark plug sockets have thinner walls than a standard socket. They come with a hex head on the back end so you can turn with a wrench if you cannot use a ratchet or swivel extension to reach the plug. Many come with large markings to easily identify the socket size. A knurled non-slip surface machined into the outside of the socket offers a better grip to help you start spark plug threads by hand.
  • Six-point vs. 12-point sockets. Spark plug sockets usually are six-point to prevent rounding off spark plugs that are tough to remove. Some newer imports need extra-thin-walled 12-point sockets to reach spark plugs hidden in tight corners.
  • Swivel (universal or flex-head) spark plug sockets have a flexible joint to reach around obstacles or get to spark plugs deep in the engine bay. Look for swivel sockets with a built-in extension that helps access difficult-to-reach spark plugs.
• Ratchet wrench: Available in assorted drive sizes (most common are 1/4-in., 3/8-in. and 1/2-in.) and configurations (short, standard, long-handled and flex-head). For removing spark plugs, a longer handle flex-head ratchet is the way to go, but a standard ratchet will work just fine. Ratchets with 72 teeth work better in confined spaces. “Quick release” models make removing sockets easier when your hands are greasy.
• Torque wrench: This tool should be your go-to for tightening spark plugs, especially in cast aluminum cylinder heads. Although a flex-head torque wrench is best for installing spark plugs, a fixed-head torque wrench will also work. Look for a “click” style torque wrench that can be felt as well as heard when the proper torque is reached. These all-metal, reversible wrenches are also easy to adjust and read standard and metric scales.

Best Spark Plug Gap Gauge

The one-piece, zinc alloy Weewooday Spark Plug Gap Gauge fits the bill nicely. Like most spark plug gap gauges, this simple tool has standard readings on one side and metric on the other side.