GM 12681657 Plug

When replacing spark plugs, remove each one at a time following a particular procedure. To access the spark plugs for the front cylinder bank (BANK 2) in models 2009 and up you might have to remove intake manifold. A spark plug socket, extensions, gap gauge for gap adjustment and torque wrench for proper tightening are necessary tools for this job. Prior to removing them from the package adjust the gaps of the new spark plugs to specifications then replace them one at a time so as not to cause mix-up. Before starting the vehicle allow it to cool off completely, inspect new plugs for defects and correct gaps if necessary. It is important to check for any cracks in porcelain insulator. Ensure that you do not scratch off platinum or iridium coating on electrodes. Take out ignition coils and if possible blow compressed air around the spark plugs in order to prevent dirt or other impurities from entering into the engine cylinders. With a sparkplug socket, unscrew and remove old sparkplugs. Compare with reference materials to evaluate state of engine operation using old plugs from car's engine. Apply anti-seize compound on threads of new plugs and tighten them using a torque wrench or ratchet; utilize rubber hose as an instrument against crossthreading while screwing them into place. Put back ignition coil and repeat this process with remaining sparkplugs.