BMW 1 Series/3 Series E87/E90/E91 Front Oxygen Sensor 11787530282 Original quality, comes with 0258007273

Front oxygen sensor for BMW 1 Series E87 (2004–2011) and 3 Series E90/E91 (2005–2012), part number 11787530282, with cross-number 0258007273; fits 2.0L–3.0L engines. Function: real-time monitoring of exhaust oxygen, feedback to ECU to optimize fuel injection, improving combustion efficiency and reducing emissions. Replacement difficulty moderate; use dedicated oxygen sensor socket to avoid thread damage. If fuel consumption rises, acceleration is sluggish, or emission fault light on, replace.