Audi A4 B9 A5 F5 NOX Lambda Oxygen Sensor 2.0 TDI Diesel Engine 8W0907807AM

Visual condition of the part

The product shows signs of use visible in the photos.

Audi A4 B9 A5 F5 NOX Lambda Oxygen Sensor 2.0 TDI Diesel Engine is a precision oxygen sensor designed for diesel systems, responsible for accurate exhaust gas composition measurement and the proper operation of the exhaust treatment system. As an item from the Lambda sensors and O2 sensors group, it supports stable engine operation, reduces emissions, and helps maintain optimal combustion parameters in the diesel engine.

Specifications and technical data

• SKU: 8W0907807AM-1
• Mark: Audi
• Condition: Used
• OEM Part Number: 8W0907807AM
• Substitutable numbers: 8W0907807AM, 8W0 907 807 AM
• Fuel type: Diesel
• Category: Oxygen Sensors

Purpose and function in the exhaust system

The offered oxygen sensor is dedicated to Audi A4 B9 generation and Audi A5 F5 generation models with a 2.0 TDI diesel engine. Its task is to continuously measure the oxygen and nitrogen oxide content in the exhaust gases, which allows the engine control unit to precisely adjust the fuel dosage and the operation of the exhaust treatment system. As a result, the engine maintains stable performance, and the emission of harmful exhaust components is kept within the limits specified by the manufacturer.

A functional NOX / lambda sensor is crucial for the proper operation of the diesel particulate filter, the catalytic converter, and the entire diesel engine control system. Replacing a worn-out part with an original Audi component reduces the risk of the engine entering limp mode, prevents excessive fuel consumption, and helps maintain compliance with emission standards.

Benefits of using an original Audi sensor

Using an original oxygen sensor in the Audi A4 B9 / A5 F5 ensures:

• proper cooperation with the factory engine control unit software,
• stable operating parameters of the 2.0 TDI unit across the full load range,
• better control over the combustion process and exhaust emissions,
• reduced risk of exhaust system-related errors.

For the user, this means more predictable vehicle behavior, a reduction in costly repairs resulting from operation with incorrect parameters, and the ability to maintain the efficiency of the exhaust system for a longer period. In the case of diesel engines, a properly functioning NOX / lambda sensor is one of the key elements affecting the service life of the auxiliary equipment.

Characteristics and application in a diesel engine

The presented component operates in a Diesel-powered system, where requirements regarding exhaust gas composition control are particularly high. The sensor works with the engine control system, providing it with information necessary for:

• precise fuel dosing under various load conditions,
• proper operation of emission reduction systems,
• monitoring the state of the exhaust system for OBD diagnostics.

Thanks to this, it is possible to maintain a balance between performance, fuel consumption, and emission levels. If errors related to the NOX system or lambda sensor appear, replacing it with a functional element from this group is one of the basic service steps.

Condition, origin, and installation aspects

The offered sensor comes from the Audi parts line and is a dismantled component, which allows combining an attractive purchase cost with the preservation of factory specifications. The used condition means that the component has been previously operated but is suitable for further use after proper verification. For many users, this is a reasonable compromise between price and quality, especially in the case of advanced electronic components.

Before installation, a standard service procedure is recommended: checking the wiring harness, connectors, and reading diagnostic errors to confirm that the oxygen sensor is indeed the cause of the problems. A properly selected element from the Lambda sensors and O2 sensors group allows for installation without the need for system modifications, which shortens repair time and reduces the risk of additional faults.

Selecting a used sensor and technical knowledge

When choosing a used oxygen sensor for an Audi, it is particularly important to match it according to the engine version and exhaust system configuration. In practice, this means paying attention to the manufacturer's markings, compatibility with the given model generation, and the fuel type. To better understand how to safely select used modules and sensors, it is worth checking the Global Parts guide: Used automotive electronics on board – why is it worth choosing second-hand ECU modules and sensors?, which discusses issues of compatibility, selection by markings, and practical installation examples.

If you are planning a comprehensive repair or upgrade of the engine area in your Audi and need other elements from the same group, such as additional oxygen sensors, pre- and post-catalytic converter sensors, or exhaust gas monitoring components, check the available parts in the Audi Lambda sensors and O2 sensors category.