Audi A4 B9 AdBlue Additive Tank Reservoir 2.0 TDI 8W0131878AM

Audi A4 B9 AdBlue Additive Tank Reservoir 2.0 TDI is an original AdBlue additive tank designed for the fuel supply system in modern Audi diesel engines. This part belongs to the Fuel tanks and filler pipes category and is a key component of the exhaust emission reduction system in your A4 B9 with a 2.0 TDI engine. Thanks to its factory design, it ensures proper storage of the additive and stable cooperation with the vehicle's electronics.

Specifications and technical data

• SKU: 8W0131878AM
• Mark: Audi
• Condition: Used
• OEM Part Number: 8W0131878AM
• Substitutable numbers: 8W0131878AM, 8W0 131 878 AM
• Part type: Fuel Tank
• Category: Fuel Tanks & Filler Necks

Purpose and function in the fuel and emission system

The presented AdBlue additive tank is responsible for the safe storage of the urea solution used in the Selective Catalytic Reduction (SCR) system in the Audi A4 B9 generation with a 2.0 TDI unit. A properly functioning tank allows for precise dosing of the additive into the exhaust system, which translates into reduced nitrogen oxide emissions and ensures the vehicle complies with current environmental standards.

Thanks to its factory design, the component is optimized for compatibility with the fuel system and engine control unit, ensuring stable pressure and appropriate operating conditions for the pump and AdBlue supply lines.

Construction and fitment for Audi A4 B9 2.0 TDI

The tank has been designed specifically for the Audi A4 B9 platform, which guarantees proper mounting in the chassis, compatible connections, and correct routing of lines within the additive supply system. The construction provides for integration with factory sensors and equipment, ensuring full functionality of the fluid level and temperature monitoring system after installation.

Original origin means maintaining the geometry and parameters specified by the manufacturer, which minimizes the risk of leaks, control unit errors, and adaptation problems. This is particularly important in vehicles equipped with advanced on-board diagnostic systems.

Benefits of using an original AdBlue tank

Choosing a factory AdBlue additive tank for an Audi translates into a number of practical advantages in daily operation:

• secure fitment to the mounting system and lines in the A4 B9 2.0 TDI model,
• proper cooperation with sensors and electronics responsible for additive dosing,
• stable operation of the SCR system and reduced risk of the engine entering limp mode,
• maintenance of factory emission parameters and correct operation of OBD diagnostics.

As a result, the fuel and emission system maintains the characteristics intended by the manufacturer, and the driver avoids problems with error messages and performance drops resulting from improper AdBlue system operation.

Condition, verification, and preparation for installation

The item is offered as a used part, which allows for an economical repair of the system while maintaining original build quality. The tank comes from disassembly and is intended for reinstallation in a vehicle after prior verification of compatibility with the part number and the configuration of the specific Audi A4 B9 unit.

Before purchasing, it is recommended to verify compatibility based on vehicle data and manufacturer markings to ensure full compliance with the existing fuel and emission system and to avoid the need for installation modifications.

Integration with other fuel system components

A functional AdBlue additive tank works with the pump, lines, and additive injector, creating a cohesive system responsible for emission reduction. In the case of comprehensive fuel and emission system maintenance, it is worth expanding your knowledge on the diagnostics and operation of these components – you can find practical tips in the article Fuel system – injectors, pumps, and fuel tank: maintenance and regeneration, which discusses part selection by number, typical symptoms of failure, and principles of proper regeneration.

If you are planning a comprehensive repair or upgrade of the fuel supply and storage area in your Audi and need other elements from the same group, such as additional tanks, filler pipes, or venting elements, check the available parts in the Audi fuel tanks and filler pipes category.