Genuine OEM Audi Engine Timing Belt Idler Pulley, part number 06D109244E. This essential component is part of the engine's timing belt system, responsible for guiding the timing belt and maintaining proper tension to ensure precise valve timing. Its robust construction and integrated bearing are designed for continuous, high-speed rotation. Measuring approximately 28mm in diameter and 33mm in height, using a genuine OEM idler pulley guarantees the correct bearing quality, dimensions, and material strength, which are crucial for the reliable operation and longevity of the engine's timing system, preventing catastrophic engine damage.