2012 Nissan Sentra Owner's Manual - Page 305

SPARK PLUGS 1. Visually inspect the belt for signs of unusual wear, cuts, or fraying. If the belt is in poor condition, have it replaced or adjusted by a NISSAN dealer. 2. Have the belt checked regularly for condition. WARNING Be sure the engine and 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. If replacement is required, see your NISSAN dealer for assistance. SDI1895 REPLACING SPARK PLUGS Iridium-tipped spark plugs (if so equipped) A It is not necessary to replace iridium-tipped ᭺ spark plugs as frequently as conventional type spark plugs because they last much longer. Follow the maintenance log shown in the "NISSAN Service and Maintenance Guide". Do not service iridium-tipped spark plugs by cleaning or regapping. ● Always replace spark plugs with recommended or equivalent ones. 8-18 Maintenance and do-it-yourself