At the top of the cylinder head of an MX5 NB (1998–2000), the camshafts determine when and how far the intake and exhaust valves open. This allows the fresh fuel-air mixture to enter and the burned gases to be expelled. This movement is driven by the timing belt and tensioners, which ensure the crankshaft and camshafts rotate in precise sync. As a result, play, wear, or incorrect timing is not only audible in the valve train but can also directly affect engine smoothness and performance.
