Lambda Sensor BMW F20 F21 F30 F31 LCI Petrol Oxygen Probe Exhaust 8631047

Visual condition of the part

The product shows signs of use visible in the photos.

Lambda Sensor BMW F20 F21 F30 F31 LCI Petrol Oxygen Probe Exhaust is an original component from the Lambda sensors and O2 sensors group, designed for petrol engines in popular BMW 1 and 3 series models after the facelift. This used OEM part ensures factory-fit, proper cooperation with the vehicle's electronics, and stable control of the air-fuel mixture composition.

Specifications and technical data

• SKU: 8631047-1
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 8631047
• Substitutable numbers: 8631047, 11788631047, 0258027103, KD
• Fuel type: Petrol
• Category: Oxygen Sensors

Purpose and function in a petrol system

The lambda sensor in a BMW petrol engine is responsible for precise measurement of oxygen content in the exhaust gases, which allows the engine control unit to continuously adjust the fuel dose. As a result, the power unit maintains the correct mixture composition, which translates into:

• efficient catalytic converter operation and reduced exhaust emissions,
• stable engine performance across the entire rev range,
• more predictable throttle response and correct dynamics,
• maintaining fuel consumption at the intended level.

In BMW F-series vehicles, the lambda sensor is a key sensor in the engine control unit's feedback loop, which is why its proper operation has a direct impact on operational safety and the durability of the power unit.

Advantages of using an original BMW sensor

Using an original lambda sensor from the BMW group ensures full compatibility with the controller software and engine operating parameters. In practice, this means:

• no need for electrical or mechanical installation modifications,
• correct signal interpretation by the ECU controller,
• stable fuel trim values in closed-loop operation mode,
• reduced risk of errors related to the mixture and catalytic converter.

A used OEM part with preserved original signal characteristics is particularly beneficial where compliance with factory injection and ignition maps is important, without experimenting with replacements of uncertain parameters.

Condition, verification, and selection based on technical data

The item is offered as a used BMW lambda sensor, which allows for reducing repair costs while maintaining the manufacturer's original specifications. Before installation, standard system diagnostics are recommended, including checking the wiring harness, connectors, and exhaust system tightness so that the new sensor in the vehicle operates under proper conditions.

When selecting a lambda sensor, it is worth using the OEM part number and interchangeable numbers, as well as vehicle data (model, generation, petrol engine type). Such an approach minimizes the risk of thread, cable length, or connector type mismatch and facilitates installation in a specific BMW F-series unit.

Integration with electronics and OBD diagnostics

In modern BMW F-series models, the lambda sensor works with the OBD system, enabling ongoing monitoring of the mixture composition and exhaust system efficiency. A functional sensor:

• limits the appearance of errors related to a mixture that is too rich or too lean,
• facilitates correct controller adaptation after intake or exhaust system repairs,
• supports maintaining compliance with emission standards provided for a given model.

For users who want to better understand the rationale for using used sensors and modules, practical tips on selection by OEM numbers, hardware and software compatibility, and installation can be found in the Global Parts guide: used automotive electronics and second-hand sensors.

Why consider a used OEM part?

In the case of lambda sensors for BMW, choosing a used OEM part is often a reasonable compromise between cost and quality. You receive a component designed exactly for a given powertrain, without the need for adaptation or installation modifications. Additional arguments in favor of such a solution have been collected in the article: 5 reasons why a used OEM part may be better than a replacement.

If you are planning a comprehensive repair or upgrade of the engine area in your BMW and need other components from the same group, such as additional probes, O2 sensors, or related exhaust sensors, check the available parts in the category BMW Lambda sensors and O2 sensors.