Audi RS4 B8 A8 D4 High Pressure Fuel Pump 4.2 FSI Petrol CDRA 079127025Q

Audi RS4 B8 A8 D4 High Pressure Fuel Pump 4.2 FSI Petrol CDRA is an original component from the Fuel pumps and level sensors group, designed for petrol engines with high requirements for flow and pressure stability. The used high-pressure pump ensures factory-standard fuel system performance, which translates into reliable starting, smooth operation of the 4.2 FSI unit, and predictable vehicle behavior across the full load range.

Specifications and technical data

• SKU: 079127025Q
• Mark: Audi
• Condition: Used
• OEM Part Number: 079127025Q
• Substitutable numbers: 079127025Q, 079 127 025 Q, 079 127 025 AL, 079127025AL
• Fuel type: Petrol
• Category: Fuel Pumps & Sending Units

Purpose and role in the fuel system

The presented high-pressure pump is a key component of the FSI petrol engine injection system, responsible for generating the appropriate high fuel pressure in the fuel rail. In 4.2 FSI units, the use of a dedicated pump allows for maintaining stable supply parameters during dynamic driving, high RPMs, and sudden load changes.

Thanks to a design tailored to the specifics of Audi engines, the pump works in harmony with the control electronics and pressure sensors, enabling precise fuel metering. This results in proper engine refinement, predictable throttle response, and the maintenance of factory performance without the need for ECU software modifications.

Compatibility and part identification

The component comes from the Audi brand, which ensures the preservation of original geometry, mounting points, and fuel connections. This facilitates installation in place of a worn-out pump without the need for modifications to the installation, lines, or brackets. The product has an assigned OEM part number and interchangeable numbers, which allows for unambiguous identification and matching to a specific engine configuration and vehicle model year.

When selecting a pump, it is worth using the manufacturer's markings and service documentation to confirm compatibility with a given version of the 4.2 FSI unit. This ensures full compatibility with the factory control system and avoids problems with starting, ECU errors, or rough cold idling.

Operating parameters and fuel type

The pump has been designed for use with engines powered by petrol, utilizing FSI direct injection technology. The appropriate flow characteristics and operating pressure range are adapted to the requirements of the 4.2 unit, where maintaining a stable supply under high load and during prolonged highway driving is essential.

Using the correct high-pressure pump in a petrol system reduces the risk of power drops, hesitation during acceleration, and excessive load on the injectors. This solution is particularly important in sports-oriented vehicles, where repeatability of parameters and resistance to intensive use are of great significance.

Condition, installation, and operation

The offered pump is in Used condition, meaning it has been removed from a vehicle but retains the functionality required for further operation. For best results, installation by a specialized service center is recommended, as they will verify the fuel system's tightness, the correctness of the line connections, and the integration with the existing installation.

When replacing the high-pressure pump, it is also worth checking the condition of the fuel filtration, lines, and control elements to ensure stable and safe operation of the entire fuel system. A correctly selected and installed component allows for the restoration of factory engine performance without the need for costly modifications.

If you are planning a comprehensive repair or upgrade of the fuel supply area in your Audi and need other components from the same group, such as low-pressure pumps, fuel level sensors, or power modules, check the available parts in the Audi fuel pumps and level sensors category.

Selection by numbers and technical support

When purchasing a used high-pressure pump, it is particularly important to correctly match it by OEM number and interchangeable numbers, as well as to verify compatibility with the specific engine version. In practice, this means checking the markings in the service documentation or via the VIN to avoid installing the wrong variant.

If you want to deepen your knowledge about the selection and installation of sensitive used components, such as control modules or sensors working with the fuel system, the following guide will be helpful: Used automotive electronics on board – why is it worth choosing second-hand ECU modules and sensors?. You will find practical tips there regarding part identification by numbers, compatibility, and safe installation in modern vehicles.