Coolant Pipe Audi A4 B8 A5 8T 2.0 TDI Water Cooling Line 03L122157C

Audi A4 B8 A5 8T 2.0 TDI Coolant Hose Water is an original cooling system component from the Hoses, Pipes and Tubes group, designed for 2.0 TDI diesel engines in Audi A4 B8 and Audi A5 8T models. The used OEM part ensures factory geometric fit and proper coolant flow, contributing to stable engine operation.

Specifications and technical data

• SKU: 03L122157C
• Mark: Audi
• Condition: Used
• OEM Part Number: 03L122157C
• Substitutable numbers: 03L122157C, 03L 122 157 C
• Category: Hoses, Lines & Pipes

Function and Application of the Coolant Hose

The water coolant hose is responsible for the controlled transport of fluid between cooling system components, such as the engine block, radiator, and return circuit. A correctly selected hose:

• maintains system tightness under typical thermal loads of the 2.0 TDI engine,
• ensures stable coolant flow, reducing the risk of overheating,
• minimizes pressure drops in the circuit due to appropriately selected diameter and shape.

Thanks to its construction in line with factory Audi standards, the hose works with original spigots and clamps, facilitating installation and servicing.

Benefits of Using an Original Audi Hose

Using an original hose in the cooling system brings tangible operational benefits:

• Factory Fit – the hose geometry matches the original installation in the engine bay of Audi A4 B8 and A5 8T, eliminating stress and twisting during installation.
• Stable Cooling System Operating Parameters – the correct fluid flow path is maintained, supporting uniform heat dissipation from the 2.0 TDI unit.
• Compatibility with OEM Markings – the hose has a dedicated part number and interchangeable numbers, making it easier to verify compatibility with a specific vehicle configuration.

For users who want to avoid experimenting with aftermarket parts, choosing an original hose is a safe and technically predictable solution.

Product Characteristics and Condition

The offered hose belongs to the Hoses, Pipes and Tubes group, meaning it is designed to operate in an environment of operational fluids and variable temperatures. The used condition of the component allows for economical repair of the cooling system while maintaining the original installation specifications. The hose is suitable as a replacement for a worn, brittle, or mechanically damaged part in your Audi.

Selection and Compatibility with the Cooling System

To correctly select the hose for a specific engine version and year, it is worth paying attention to the OEM markings and interchangeable numbers assigned to this reference. This helps avoid problems with hose length, diameter, or bend geometry. If in doubt, comparing the shape and mounting points with the currently installed part in the vehicle can be helpful.

If you want to deepen your knowledge on how to flawlessly select used car parts and understand OEM markings, it is worth using practical advice from experts – detailed tips can be found in the article No More Wrong Purchases! How to Professionally Select Used Car Parts.

Cooling System Expansion in Audi

If you are planning a comprehensive repair or upgrade of the cooling system area in your Audi and need other parts from the same group, such as flexible hose sections, rigid guide pipes, or additional circuit branches, check the available parts in the Audi Hoses, Pipes and Tubes category.