Specific guidelines should be followed when replacing spark plugs to ensure that they are installed properly. Do not attempt to regulate the gap on platinum or iridium spark plugs since it could cause harm to its electrodes plating. These spark plugs come with pre-gapped. To replace them, you will need a spark plug socket with a rubber grommet on there so you do not chip the ceramic insulator and so you can hold onto the plug as you lower it down into the hole. When buying new ones, ensure they correspond to your vehicle's specification by referring to Specifications Section, Vehicle Emissions Control Information (VECI) label under hood or owner's manual. Avoid defective ones including those having cracks in their porcelain insulators. Take off engine covers and move hoses/components blocking access. Sometimes on V6 engines, the upper intake manifold must be taken off for rear spark plug access purposes. Just gently pull wires from old-style plug wires attached to them and unplug coil wiring first then unbolt/remove each coil if it has a coil directly over the top of the spark plug for new-style coils with rubber boots serve as connectors between each coil and its respective plug well blow dirt away using compressed air if available, remove a The Old Spark Plug Using The Correct Socket And Extension Compare old plugs against one another; this may give insight into overall engine performance condition; apply anti-seize compound only until all threads are covered; use an appropriately sized soft rubber tubing for threading; tighten according to torque specifications; reattach all cables securely after connecting wire connections done properly; put back what was removed during servicing earlier.