Torque-to-Yield Fasteners

TORQUE-TO-YIELD FASTENERS
Some fasteners on the 4 cylinder and 6 cylinder engines are "torque-to-yield" fasteners. Torque-to-yield fasteners must be replaced whenever removed and require a torque angle meter in addition to a torque wrench for proper installation. Simply put, a "torque-to-yield" fastener is designed to stretch a certain amount upon correct installation. This is why they cannot be re-used. Once stretched in position, this action cannot be repeated.