The Mercedes W204 W211 OM646 Diesel Fuel Rail is a fuel supply system component designed for diesel engines, engineered by the manufacturer for stable engine operation. A used fuel rail allows for an economical yet technically correct repair of the common rail system in Mercedes vehicles with an OM646 engine.
Specifications and technical data
- SKU: A6460700395
- Mark: Mercedes (Genuine OE)
- Condition: Used
- OEM Part Number: A6460700395
- Substitutable numbers: A6460700395, A 646 070 03 95
- Fuel type: Diesel
- Category: Fuel Injectors
Purpose and Role in the Injection System
The fuel rail in a Diesel engine is responsible for the uniform distribution of high-pressure fuel to individual injectors. A correctly selected fuel rail ensures:
- stable fuel pressure across the entire engine load range,
- precise supply to injector nozzles, which translates to smoother engine operation,
- limitation of pressure fluctuations, affecting exhaust emissions and fuel consumption.
In mid-range and premium Mercedes vehicles, such as the W204 and W211 series, the correct selection of the fuel rail is crucial for the durability of the entire common rail system.
Compatibility with the Injector Nozzle System
This product belongs to the Injector Nozzles category, meaning it is an integral part of the fuel line that works directly with the injectors. A suitable fuel rail:
- ensures proper operating conditions for injectors in a diesel engine,
- minimizes the risk of uneven cylinder operation caused by pressure differences,
- supports correct fuel atomization, which impacts performance and fuel economy.
Thanks to its adaptation to a specific generation of the OM646 unit, the fuel rail works with the factory control electronics, facilitating diagnostics and subsequent service.
Benefits of Using an Original Mercedes Fuel Rail
Choosing a fuel rail from the vehicle manufacturer is the preferred solution in professional workshops. The main advantages include:
- factory geometry and mounting points – facilitating installation in the engine bay without modifications,
- compliance with OM646 engine operating parameters – important for high operating pressures in Diesel systems,
- predictable fuel supply system behavior after component replacement, simplifying further diagnostics.
A used fuel rail is a good choice when the existing component has suffered mechanical damage or internal wear, and the priority is to maintain correct engine operating parameters at a reasonable repair cost.
Diagnostics and Prevention of the Injection System
When experiencing issues with the common rail system – such as starting difficulties, power loss, or excessive smoke – a comprehensive diagnostic should be performed, covering both the fuel rail and the injectors. A detailed discussion of typical symptoms and the consequences of neglect can be found in the article diesel injector faults – how to recognize them and what their neglect entails, which helps to better understand the relationships between individual fuel system components.
Other Mercedes Injector Nozzles
If you are also looking for other Mercedes injector nozzles suitable for various models and diesel engine configurations of this brand, check out our dedicated category: Mercedes injector nozzles. This will allow you to easily compare available solutions and select components that match the specifics of your fuel supply system.
