Audi A4 B8 Fuel Line Fuel Feed Return Pipe Hose 2.0 Petrol 06H133986H

Audi A4 B8 Fuel Line Fuel Feed Return Pipe Hose 2.0 Petrol is an original fuel system component designed for petrol engines in the Audi A4 B8 generation. The precisely selected geometry of the line ensures stable fuel return to the system, which promotes smooth engine operation and proper compatibility with factory equipment.

Specifications and technical data

• SKU: 06H133986H
• Mark: Audi
• Condition: Used
• OEM Part Number: 06H133986H
• Substitutable numbers: 06H133986H, 06H 133 986 H
• Fuel type: Petrol
• Category: Hoses, Lines & Pipes

Purpose and function in the fuel system

The described fuel return pipe operates in the fuel circuit of the petrol engine, responsible for the safe discharge of excess fuel from the fuel rail or supply module back to the tank. A properly selected line in this section of the system:

• stabilizes fuel pressure in the installation,
• reduces the risk of air ingress and fuel dose fluctuations,
• supports smooth injector operation under various engine loads.

Thanks to this, the petrol supply system maintains parameters close to factory specifications, which is important for both performance and the refinement of the 2.0 unit.

Construction, fitment, and installation

The line belongs to the Lines, hoses, and pipes group of components, meaning its construction is optimized for resistance to petrol and typical operating conditions in the engine bay. The shape and connection diameters are adapted to the factory Audi system, which facilitates installation without the need for modifications to the installation.

In practice, this means that by following the correct service procedure:

• connections with other fuel system components remain leak-proof,
• the line does not require additional adapters or modifications,
• replacement time can be limited to a standard workshop operation.

Benefits of using an original Audi line

Using a fuel return line dedicated to the Audi A4 B8 allows for maintaining the consistency of the entire supply system with factory technical documentation. This is particularly important in modern petrol units, where fuel pressure and flow parameters are strictly controlled by the engine control unit.

Key advantages of this solution include:

• compatibility with factory equipment – the line works with original connectors and mounting brackets,
• maintaining correct fuel system operating parameters,
• reducing the risk of leaks, seepage, and starting problems after long periods of inactivity.

Application in service and diagnostics

Replacing the fuel return pipe is recommended in situations where signs of abrasion, micro-cracks, leaks, or mechanical damage resulting from previous repairs in the engine bay appear. In the case of Audi A4 B8 petrol units, a properly functioning return line affects:

• fuel pressure stability during rapid load changes,
• engine operation at idle and during startup,
• operational safety under high-temperature conditions.

For workshops specializing in the Audi brand, using a dedicated line facilitates diagnostics – it eliminates variables resulting from non-original solutions and allows focusing on actual fuel system faults.

System expansion – related components

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

If you are interested in a broader context of the operation of modern petrol units, turbochargers, and charge air cooling systems, the Global Parts guide on selecting equipment for the B58 engine family may be helpful – you can find it in the article BMW B58 code – checklist before buying a turbocharger and intercooler.