To change a spark plug, you need a torque wrench, wire-type feeler gauge, ratchet wrench and spark plug socket. A rubber grommet lines that socket to safeguard the porcelain insulator of the spark plug and hold it during you insert it into the hole for the spark plug. To replace them, purchase new ones set their gap correctly and then install one at a time. For your specific vehicle, ensure that you get proper plugs found on the Vehicle Emissions Control Information (VECI) label under the hood. Examine all new plugs for blemishes with electrode gaps checked as well. If not so, use the curved side electrode slightly bending notched adjuster on its feeler gauge body if needed. Now work on one spark plug at a time to avoid problems from mixing up threads in wires while fixing other parts Remove one wire and boot from a single spark plug; but before going forward, clear away any dirt or foreign matter from around the area of this equipment if there exists compressed air Take out each of these old plugs and compare them with one another in order to determine how well engine is running In order to prevent cross-threading when installing new plugs, slip 3/16-inch ID rubber tubing over it until thread tighten fit short pieces followed by twisting motion Place boot on end of new sparkplug firmly by twisting it onto that end Follow above steps for changing rest of plugs individually instead of mixing up cables.