Mercedes-Benz W211/S211 Front Oxygen Sensor A0035427318 850mm OEM Replacement

This front oxygen sensor is designed for Mercedes-Benz W211 (2002–2009 E-class sedan) and S211 (2002–2009 E-class wagon) with M272/M273 engines (2.5L, 3.0L, 3.5L). Monitors oxygen content in exhaust, feeds ECU to adjust air-fuel ratio for efficient combustion and reduced emissions. OEM A0035427318, also compatible with 0258007161; cross-check with Bosch or OEM stock. Replacement difficulty: medium; disconnect the battery negative first; note harness routing; recommended to use a dedicated socket to avoid thread damage. Sensor harness length: 850mm; fits original layout; no extra extension required; reduces installation time.