The Mercedes W221 OM642 CDI Fuel Injector is an original injector nozzle designed for OM642 diesel engines in W221 S-Class models. This component ensures precise diesel fuel metering, stable engine operation, and correct combustion parameters in the common rail system.
Specifications and technical data
- SKU: A6420701987
- Mark: Mercedes (Genuine OE)
- Condition: Used
- OEM Part Number: A6420701987
- Substitutable numbers: A6420701987, A 642 070 19 87
- Fuel type: Diesel
- Category: Fuel Injectors
Application in OM642 CDI Engines
The presented fuel injector operates within a Diesel fuel supply system, characteristic of OM642 CDI units. It is responsible for:
- precise fuel atomization in the combustion chamber under high operating pressure,
- maintaining smooth operation of all cylinders,
- stable cold starts and proper throttle response across the entire RPM range.
A properly functioning injector nozzle reduces smoke, improves engine running smoothness, and helps maintain the factory performance of the OM642 unit in the Mercedes S-Class W221.
Technical Characteristics of the Injector Nozzle
The fuel injector offered here belongs to the Injector Nozzles category, meaning it is a precision component operating under very demanding pressure and temperature conditions. Its design is adapted for:
- common rail systems in Mercedes diesel engines,
- operation with diesel fuel meeting specifications for CDI units,
- precise fuel dose control by the engine control unit, accounting for multiple injection phases.
Proper matching of the injector nozzle to the specific engine is crucial for maintaining correct rail pressure, uniform combustion, and protecting components such as pistons, valves, and the diesel particulate filter.
Benefits of Using an Original Mercedes Injector
Choosing a fuel injector specifically designed for the Mercedes W221 OM642 CDI allows for maintaining performance parameters close to factory specifications. Key advantages include:
- compatibility with the fuel system and Mercedes engine control unit software,
- appropriate spray pattern tailored to the OM642 engine's combustion chamber,
- reduced risk of incorrect fuel metering compared to random aftermarket replacements.
A correctly selected component helps reduce fuel consumption, maintain smooth idling, and minimize the risk of damage resulting from improper injection.
Part Condition and Installation Aspects
The offered fuel injector is a used part, allowing for an economical repair of the fuel system while maintaining proper fitment for the OM642 CDI engine. Prior to installation, it is recommended to:
- perform professional diagnostics of the injection system,
- check the seals of the fuel lines and common rail,
- install at a specialized workshop with access to appropriate diagnostic equipment.
Proper installation and adaptation of the injector in the engine control unit are essential for achieving stable operating parameters and avoiding system errors.
Diagnostics and Preventive Maintenance of the Injection System
To better understand the symptoms of worn injector nozzles and the consequences of neglecting them, it is worth consulting the guide: Diesel Injector Faults – How to Recognize Them and What Neglecting Them Entails. This article discusses typical symptoms, potential engine consequences, and diagnostic methods, making it easier to decide on injector replacement.
Other Mercedes Injector Nozzles
If you are also looking for other Mercedes injector nozzles for different models or engine configurations, check out the Mercedes injector nozzles available in our store. This will allow you to easily compare available solutions within the same category and brand, selecting the component best suited for your specific vehicle.
