Audi A4 B8 A5 8T Brake Servo Vacuum Pipe Hose Line Return Valve 8K0611931BT

Audi A4 B8 A5 8T Brake Servo Vacuum Pipe Hose Line Return Valve is an original vacuum system component responsible for providing stable supply to the brake servo in your Audi. Thanks to its precise OEM design, the hose ensures proper brake assistance, which translates into predictable pedal response and safe deceleration. This solution is dedicated to specific models, guaranteeing a perfect fit for the factory geometry of the braking system.

Specifications and technical data

• SKU: 8K0611931BT
• Mark: Audi
• Condition: Used
• OEM Part Number: 8K0611931BT
• Substitutable numbers: 8K0611931BT, 8K0 611 931 BT
• Category: Vacuum Pumps

Function and role in the braking system

The brake servo vacuum hose is responsible for transporting vacuum from the vacuum generation system to the servo, which amplifies the force applied to the brake pedal. A properly functioning hose:

• ensures stable brake assistance across the full range of engine loads,
• reduces the risk of decreased braking efficiency during sudden braking,
• maintains the tightness of the vacuum system, minimizing energy loss,
• supports smooth servo operation, which improves brake pedal feel.

Thanks to a design consistent with Audi factory standards, the hose works with the original servo and other vacuum system components without the need for modifications.

Compatibility and fit for Audi A4 B8 / A5 8T

The hose has been designed specifically for the Audi A4 B8 and Audi A5 8T platform, which means its geometry, connection diameters, and routing are adapted to the factory layout of components in the engine bay. Such a fit:

• facilitates installation in existing brackets and guides,
• reduces the risk of rubbing against other components,
• ensures correct positioning relative to the servo and the vacuum source.

The original Audi origin allows for consistency with other braking and vacuum system components, which is particularly important for repairs performed according to the manufacturer's guidelines.

Characteristics of the used component

The offered vacuum hose comes from dismantling and is a used part, which represents a reasonable compromise between repair costs and maintaining OEM specifications. This type of part allows you to:

• restore factory operating parameters of the brake servo,
• avoid fitment issues typical of universal replacements,
• maintain the original routing of hoses in the engine bay.

When selecting a hose, it is worth verifying compatibility using the manufacturer's markings and comparing the shape and connection points with the part currently installed in the vehicle to ensure full compatibility.

Importance of a proper vacuum system

A functional brake servo vacuum hose has a direct impact on driving safety. Leaks or damage in this area can result in:

• increased force required to press the brake pedal,
• longer braking distance,
• irregular servo operation and a variable pedal "bite" point.

Replacing the hose with an original part from the same design group allows you to restore stable assistance and maintain predictable braking system behavior in daily use.

Service expansion and part selection by OEM

During comprehensive vehicle maintenance, it is also worth paying attention to other components working with engine power and control systems. For help with component selection based on manufacturer markings and understanding the relationship between the fuel system and engine operation, see the article: Fuel system – injectors, pumps, and fuel tank: maintenance and regeneration, which discusses diagnostics, selection by manufacturer numbers, and operating principles.

If you are planning a comprehensive repair or upgrade of the braking zone in your Audi and need other elements from the same group, such as vacuum lines, servo supply elements, or components working with the vacuum system, check the available parts in the Audi vacuum pumps category.