Mercedes W204 W211 Fuel Pressure Regulator Valve OM642 Diesel A6420740184

Mercedes W204 W211 Fuel Pressure Regulator Valve OM642 is a precision component of the diesel engine fuel system, designed to operate in the demanding environment of diesel units. It is responsible for stabilizing fuel pressure in the high-pressure rail, which translates into smooth engine operation, correct injection dosage, and predictable performance. A used component from this group allows for an economical yet technically sound repair of the fuel system in Mercedes vehicles.

Specifications and technical data

• SKU: A6420740184
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6420740184
• Substitutable numbers: A6420740184, A 642 074 01 84
• Fuel type: Diesel
• Part type: Fuel Injector Pump
• Category: High Pressure Fuel Pumps

Purpose and function in the fuel system

The fuel pressure regulator in the OM642 diesel engine operates directly in the high-pressure circuit, working in conjunction with the pump and injectors. Its task is to:

• maintain the set pressure value in the fuel rail under various load conditions,
• ensure stable operation of the injectors during start-up and acceleration,
• limit pressure fluctuations that can cause jerking, power loss, or engine control unit errors.

Thanks to the proper operation of this component, the diesel fuel system maintains appropriate dynamics, and the power unit reacts predictably to the driver's commands.

Technical category and operating characteristics

The product belongs to the High-pressure fuel pumps group, which means it is designed to work with systems generating very high operating pressures typical for modern diesel engines. The fuel pressure regulator valve:

• operates in a Diesel fuel environment,
• is adapted to the operating characteristics of the OM642 engine family,
• works with the electronic engine control unit, which corrects the injection dosage based on the sensor signal.

Such a solution allows for precise control of the combustion process, which helps maintain proper engine refinement and reduce fuel consumption.

Benefits of using an original Mercedes component

The fuel pressure regulator dedicated to Mercedes W204 and W211 models ensures:

• factory fitment to the vehicle's fuel system,
• compatibility with the operating parameters of the high-pressure pump and injectors,
• proper cooperation with the engine control unit software.

Choosing an original Mercedes solution reduces the risk of starting problems, uneven idling, or the appearance of fuel pressure-related errors. A used component of this class is a reasonable alternative to new parts, especially for maintenance repairs of older vehicles.

Application in OM642 diesel engines

The OM642 diesel engines used in Mercedes W204 and W211 models utilize an advanced injection system, in which the fuel pressure regulator valve is one of the key components. A correctly selected element:

• helps maintain proper pressure across the entire RPM range,
• influences the engine's refinement under low and high loads,
• promotes the maintenance of stable combustion parameters over a long period of operation.

For users of diesel vehicles, this means more predictable car behavior and a lower risk of costly failures related to the injection system.

Technical support and component selection

When selecting a fuel pressure regulator for a specific Mercedes vehicle, it is worth using the manufacturer's markings and vehicle data to ensure full compatibility with the injection system. Detailed information on diagnostics, selection based on manufacturer markings, and operating principles can be found in the article Fuel system – injectors, pumps, and fuel tank: maintenance and regeneration, which discusses practical aspects of working with diesel systems.

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