老款奔驰点火线圈 0221506002 — 替换0001587003/0001587503，适配W140

The ignition coil for the older Mercedes-Benz W140 chassis with M104 4-cylinder engine, OEM 0221506002, directly replaces 0001587003 and 0001587503. This part uses high-density epoxy resin encapsulation; copper windings thicker than OEM parts; tested to have superior high-temperature and vibration resistance, with life close to OEM. Core function is to raise 12V low voltage to tens of kilovolts to ignite the spark plug; stable output and resistant to moisture. Installation replacement difficulty is medium; recommended to disconnect the negative battery terminal before removing the old coil.