Genuine OEM Jaguar Engine Valve Spring, part number AJ813889. This crucial component is an integral part of the engine's valve train, responsible for closing the intake and exhaust valves precisely after they have been opened by the camshaft. Proper valve spring function is essential for maintaining optimal engine performance, compression, and fuel efficiency. Located within the cylinder head, each spring ensures the valve returns to its seat reliably. Weighing just 0.03 kg, this small part plays a vital role in engine operation. Choosing a genuine OEM valve spring guarantees the correct spring rate, material fatigue resistance, and factory tolerances for long-lasting and reliable engine performance.