1178 7573 321 Oxygen Sensor for BMW 520i E60 N46 2007-2009

◆ This oxygen sensor is a direct replacement for the original BMW unit, designed to measure oxygen concentration in the exhaust stream and provide feedback to the engine control unit for air-fuel ratio correction.

◆ The OEM reference number is 1178 7573 321 (11787573321). It is a heated lambda sensor with an overall cable length of approximately 1070 mm .

◆ The sensor is engineered to OEM standard dimensions for direct fitment into the exhaust location without modification.

◆ It is primarily designed for the BMW 5 Series E60/E61 with the N46T 2.0L engine, specifically the 520i model produced from 09/2007 through 12/2009 . Additional compatibility data lists the E60 LCI, E61, E63, E64, E65, and E66 series .

◆ This product is an oxygen sensor manufactured to meet original quality standards for signal accuracy, fit, and durability.

◆ Part Number: 1178 7573 321 / 11787573321

◆ Component Type: Oxygen Sensor / Lambda Sensor

◆ Vehicle Make: BMW

◆ Primary Fitment: 520i (E60/E61) with N46T engine

◆ Cable Length: Approx. 1070 mm

◆ Production Range: 09/2007 – 12/2009

◆ Note: Verify connector shape and specific engine variant against your vehicle's original sensor before ordering

◆ OEM Standard Fit: Manufactured to exact original specifications for a direct, hassle-free replacement.

◆ Accurate Air-Fuel Feedback: Provides reliable oxygen concentration data to the ECU, supporting proper fuel injection control and emissions performance.

◆ Heated Design: Integrated heater brings the sensor to operating temperature quickly for efficient closed-loop fuel control.

◆ Durable Construction: Built with materials resistant to exhaust heat, contamination, and vibration.

◆ BMW 5 Series E60 (LCI): 520i (N46T), 09/2007–12/2009

◆ BMW 5 Series E61: 520i (N46T), 09/2007–12/2009

◆ BMW 5 Series E60/E61: broader compatibility listed for 04/2006–12/2009

◆ BMW 6 Series E63/E64: listed compatibility

◆ BMW 7 Series E65/E66: listed compatibility

◆ Note: Fitment varies by engine variant and market. Verify against your vehicle's original part number and production year before ordering.

Q1: Is this a genuine BMW part?

A: The 11787573321 reference is the original equipment part number. Both genuine BMW and aftermarket equivalents are available that match the original fit and function.

Q2: How do I confirm if it fits my vehicle?

A: Check your vehicle’s existing oxygen sensor. If it is stamped with 11787573321 or 1178 7573 321, this replacement will fit. Also confirm your vehicle is a BMW 520i (E60/E61) with the N46T engine, produced within the 09/2007–12/2009 range .

Q3: What are the symptoms of a failing oxygen sensor?

A: Common signs include a check engine light with oxygen sensor-related fault codes, decreased fuel economy, rough idle, and failed emissions testing. A diagnostic scan can confirm which sensor circuit is faulty before replacement.