Audi RS4 B7 Water Coolant Return Pipe Hose Line 4.2 FSI 8E2819371AG

Audi RS4 B7 Water Coolant Return Pipe Hose Line 4.2 FSI is an original cooling system component designed for the precise return of coolant to the circuit. Thanks to its factory geometry and perfect fit for the 4.2 FSI unit, it ensures stable engine thermal conditions and proper cooperation with other cooling system components. This used OEM part is a sensible choice for drivers looking for a proven, compatible solution rather than random aftermarket replacements.

Specifications and technical data

• SKU: RHD-8E2819371AG
• Mark: Audi
• Condition: Used
• OEM Part Number: 8E2819371AG
• Substitutable numbers: 8E2819371AG, 8E2 819 371 AG
• Part type: Hose
• Category: Coolant Hoses

Purpose and function in the cooling system

This coolant return pipe has been designed specifically for operation in the 4.2 FSI engine cooling system of the Audi RS4 B7. It is responsible for the directional flow of coolant in the return part of the circuit, which is crucial for:

• maintaining proper coolant circulation under high thermal loads,
• preserving a stable operating temperature of the power unit,
• correct cooperation with the radiator, water pump, and other hoses.

Thanks to its factory profile, the pipe ensures proper routing in the engine bay, minimizing the risk of chafing, kinking, or improper flow.

Construction and fitment for Audi RS4 B7

The original pipe from the Cooling system pipes and hoses group is constructed with the demanding operating conditions of the high-performance 4.2 FSI unit in mind. The materials used are resistant to:

• elevated temperatures generated by a high-power engine,
• contact with coolant during long-term operation,
• vibrations and mechanical stresses typical of dynamic driving.

The precise ends of the pipe allow for a tight connection with the cooling system ports, which reduces the risk of leaks and pressure drops in the circuit. This is particularly important in cars with a sporty character, where the cooling system works under heavy load.

Benefits of using an original pipe

Using a used, original coolant return pipe in an Audi RS4 B7 allows you to maintain the factory characteristics of the cooling system. In practice, this means:

• preserving the coolant flow path designed by the manufacturer,
• secure fitment to mounts and adjacent components in the engine bay,
• reducing the risk of overheating problems resulting from improper pipe routing.

For users who value the consistency of technical solutions in an Audi vehicle, choosing an original part is a safe and predictable solution, especially in such a critical area as the cooling system.

Part condition and service application

The pipe is offered as a used part, which allows for economical repair or replacement of a damaged section of the cooling system without the need to invest in a new component. This type of solution is often chosen for:

• repairs following a coolant leak failure,
• comprehensive cooling system maintenance after engine overheating,
• restoring the original configuration in modified vehicles.

A well-chosen coolant return pipe helps restore proper system operation, which translates into engine thermal stability and operational safety.

Cooling system expansion and additional resources

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 pipes, hoses, or return sections, check out the available parts in the Audi cooling system pipes and hoses category.

To better understand how summer conditions affect cooling system efficiency and when it is worth reaching for used components, read our guide Summer heat vs. cooling system: used radiators and fans as a guarantee of savings, which will help you plan your service in a more informed and economical way.