Audi A4 B9 3.0 Diesel Fuel Return Injector Return Line Pipe Hose 059130218AR

Audi A4 B9 3.0 Diesel Fuel Return Injector Return Line Pipe Hose is an element from the Lines, hoses and pipes group, designed for the diesel engine fuel system in the Audi A4 B9 generation model. Using a pre-owned fuel return line allows for an economical yet technically correct repair of the fuel system, maintaining the factory performance characteristics of the 3.0 Diesel unit.

Specifications and technical data

• SKU: 059130218AR
• Mark: Audi
• Condition: Used
• OEM Part Number: 059130218AR
• Substitutable numbers: 059130218AR, 059 130 218 AR
• Fuel type: Diesel
• Category: Hoses, Lines & Pipes

Purpose and function in the fuel system

The fuel return line in a diesel engine is responsible for the controlled transport of excess fuel from the fuel rail or injectors back to the tank. In the 3.0 Diesel unit used in the Audi A4 B9, this is crucial for:

• stabilizing pressure in the common rail system,
• reducing fuel overheating in the circuit,
• maintaining proper injector operation under variable loads,
• increasing the durability of precision components in the fuel supply system.

A properly selected fuel return line helps maintain smooth engine operation, correct fuel metering, and predictable performance of the power unit across the entire rev range.

Compatibility with Audi A4 B9 3.0 Diesel

The offered element has been designed for the fuel system of the Audi A4 B9 with a 3.0 Diesel engine, which means matched geometry, appropriate connection diameters, and the correct resistance to operating pressure and fuel temperature. As a result, the line works with factory mounts and routing in the engine bay without the need for modifications.

Using a line consistent with the manufacturer's design reduces the risk of leaks, improper positioning in the engine bay, and unwanted vibrations that could affect the durability of other fuel system components.

Technical and material characteristics

The fuel return line belongs to the Lines, hoses and pipes group, meaning it is made of materials adapted for operation with diesel fuel. The design of the line is engineered for:

• chemical resistance to diesel fuel,
• resistance to temperature changes in the engine bay,
• tightness of connections with fuel injection system elements,
• resistance to vibrations and material fatigue during long-term operation.

This type of line has a significant impact on the safety of the fuel system operation – proper discharge of excess fuel reduces the risk of leaks and uncontrolled pressure drops.

Product condition and benefits of using a pre-owned part

The item is offered as a pre-owned part, which allows for lower repair costs while maintaining original installation characteristics. For many Audi users, this is a reasonable compromise between price and functionality, especially for components that are not subject to intense mechanical wear, but primarily to operating conditions within the fuel system.

Using an original fuel return line from dismantling facilitates installation because the factory mounting points, routing shape, and compatibility with other system components are preserved.

Fuel system expansion and related parts

If you are planning a comprehensive repair or upgrade of the fuel system area in your Audi and need other elements from the same group, such as flexible supply lines, rigid fuel pipes, or additional return sections, check the available parts in the Audi lines, hoses and pipes category.

For drivers interested in a broader look at technology development in the premium segment and the impact of drivetrain design on the selection of spare parts, the following article may be helpful: Evolution of the Mercedes S-Class – innovations and parts selection across generations.