2.5 LITER. short. A threaded rod with a drive head (such as hex, 12 point, torx, etc.) on one end used to secure the EGR Valve Cooler to it's mounting point. Accessory Drive Belt Idler Pulley Bolt. Bolt used to fasten the Engine Intake Manifold. Accessory Drive Belt Idler Pulley. Engine Intake Manifold. Exhaust Gas Recirculation (EGR) Cooler. Oil pan.