2008 Infiniti G37 Owner's Manual - Page 355

SPARK PLUGS WARNING Be sure the engine and the ignition switch are off and that the parking brake is engaged securely. CAUTION Be sure to use the correct socket to remove the spark plugs. An incorrect socket can damage the spark plugs. SDI2119 SDI2020 VQ37VHR engine 1. Visually inspect each belt for signs of unusual wear, cuts, fraying or looseness. If the belt is in poor condition or loose, have it replaced or adjusted by an INFINITI dealer. 2. Have the belts checked regularly for condition and tension in accordance with the maintenance schedule in your "INFINITI Service and Maintenance Guide". REPLACING SPARK PLUGS If replacement is required, see an INFINITI dealer for servicing. Iridium-tipped spark plugs It is not necessary to replace the iridium-tipped spark plugs as frequently as the conventional type spark plugs since they will last much longer. Follow the maintenance schedule in "INFINITI Service and Maintenance Guide", but do not reuse them by cleaning or regapping. Always replace spark plugs with recommended or equivalent ones. Maintenance and do-it-yourself 8-17