Mercedes W204 C207 X164 W639 High Pressure Fuel Pump OM642 Engine A6420701001

Mercedes W204 C207 X164 W639 High Pressure Fuel Pump OM642 Engine is a component from the High-pressure fuel pumps group, designed for operation in the OM642 diesel engine fuel supply system in selected Mercedes models. This used pump provides a functional service solution, allowing for the restoration of correct injection pressure and stable engine operation while maintaining the factory fuel system design.

Specifications and technical data

• SKU: A6420701001
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6420701001
• Substitutable numbers: A6420701001, A 642 070 10 01, 0 445 010 245, 0445010245
• Location on the vehicle: Front
• Category: High Pressure Fuel Pumps

Purpose and function in the fuel system

The presented high-pressure pump is designed to work with the OM642 engine used in Mercedes C-Class (W204), E-Class/Coupe (C207), SUV (X164) models, and W639 series commercial vehicles. It is responsible for generating sufficiently high fuel pressure for the injectors, which translates into proper diesel fuel dosing, stable idling, and predictable response to load.

The location of the pump in the front part of the vehicle facilitates service access, which is important for diagnostics, replacement, or checking the system for leaks. Thanks to the preservation of the original mounting architecture, precise fitting to factory mounts and fuel lines is possible.

Benefits of using an original injection pump

Using an original pump from the High-pressure fuel pumps group instead of a worn-out component allows for maintaining the consistency of the entire fuel supply system. In practice, this means:

• maintaining factory fuel pressure parameters in the common rail,
• better repeatability of the injection dose across the full RPM range,
• reducing the risk of starting problems on both hot and cold engines,
• lower load on other fuel system components.

For the user, this translates into more predictable operation, proper performance of the OM642 unit, and the possibility of further engine diagnostics without interference resulting from incorrect fuel pressure.

Installation aspects and fitment

The pump is designed for installation in the front part of the vehicle, in the location provided by the manufacturer. Thanks to this, the installation is based on factory mounting points, and the connection of fuel lines and controls is carried out in accordance with the original design. This facilitates the mechanic's work and limits the need for equipment modifications.

Before installation, a standard workshop procedure is recommended: checking the cleanliness of fuel lines, verifying the condition of the fuel filter, and checking the tightness of connections after starting the engine. This approach allows for fully utilizing the potential of the used pump and minimizing the risk of secondary failures.

Selection by numbers and fuel system diagnostics

The component has a dedicated OEM part number and interchangeable numbers, which facilitates verification of compatibility with a specific version of the OM642 engine and body type. When selecting, it is recommended to compare the markings with the currently installed pump or use a catalog by VIN number to avoid installation errors.

If you want to better understand the operation of the fuel supply system, diagnostic principles, and regeneration possibilities, our blog guide will be helpful: Fuel system – injectors, pumps, and fuel tank: maintenance and regeneration. You will find practical tips there regarding symptoms of pump wear, pressure testing methods, and safe operation principles.

Expansion and service of the high-pressure system in Mercedes

If you are planning a comprehensive repair or upgrade of the engine area in your Mercedes and need other elements from the same group, such as additional pumps, control elements, or components working with the common rail, check the available parts in the Mercedes high-pressure fuel pumps category.

Thanks to this, you can build a coherent service package for the OM642 unit, covering both the main high-pressure pump and other elements responsible for stable fuel supply to the engine, which facilitates long-term planning of vehicle maintenance.