Exhaust Manifold Mercedes W207 W212 OM642 Diesel Left N/S A6421400909

Mercedes W207 W212 OM642 Left Exhaust Manifold A6421400909 is an original part from the Exhaust Manifolds group, designed for OM642 diesel engines in E-Class and E-Class Coupé models. The precise geometry of the channels and factory fit to the engine head ensure stable exhaust gas removal and proper operation of the turbocharger in the diesel engine.

Specifications and technical data

• SKU: A6421400909
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6421400909
• Substitutable numbers: A6421400909, A 642 140 09 09, A6421400709, A 642 140 07 09
• Location on the vehicle: Left
• Fuel type: Diesel
• Category: Manifolds & Headers

Purpose and Function in the Exhaust System

The left exhaust manifold in the OM642 engine is responsible for collecting exhaust gases from the cylinders on one side of the block and directing them to the rest of the exhaust system. In Mercedes diesel engines, the correct shaping of the manifold channels is crucial for:

• maintaining adequate exhaust pressure before the turbocharger,
• stable operation of the boost system across a wide range of loads,
• reducing exhaust energy losses and improving diesel engine efficiency,
• reducing vibrations and thermal stresses in the cylinder head area.

Thanks to its factory design, the manifold works with the OM642 engine's accessories without requiring modifications, which simplifies servicing and reduces vehicle downtime.

Construction and Fit for OM642 Engine

This left exhaust manifold has been specifically designed for the architecture of the OM642 V-engine diesel engine. The arrangement of the spigots, flange surfaces, and mounting points conforms to the original Mercedes design, which translates to:

• secure sealing of the connection to the cylinder head and the rest of the exhaust system,
• proper exhaust gas routing from individual cylinders,
• maintaining the stock performance characteristics of the powertrain.

The appropriate shaping of the flow channels supports even loading of the turbocharger and helps maintain stable engine operating parameters under typical driving conditions.

Benefits of Using an Original Exhaust Manifold

Using an original exhaust manifold in the OM642 diesel engine allows for the preservation of the powertrain's factory operating parameters. In practice, this means:

• reduced risk of leaks at the connection to the cylinder head,
• proper exhaust gas removal and maintenance of adequate system pressure,
• better cooperation with the turbocharger and exhaust gas treatment system,
• reduction of unwanted noises resulting from manifold leaks.

For owners of Mercedes W207 and W212 models with diesel engines, choosing such a part is a way to maintain the structural integrity of the entire exhaust system and keep service costs predictable.

Installation Area and Compatibility with Diesel Systems

The manifold is designed for installation on the left side of the engine, in close proximity to the cylinder head and turbocharger. In the OM642 diesel engine, this area operates under high temperatures and significant loads, making the use of a part with factory geometry and material properties important for:

• maintaining stable temperatures in the exhaust zone,
• reducing mechanical stresses on the mountings,
• proper exhaust gas routing to downstream system components.

Such a fit is particularly important in vehicles subjected to intensive use, where the exhaust system operates under variable load and temperature conditions.

Technical Support and Additional Information

If you want to better understand how manifold selection affects the performance characteristics of the exhaust system in diesel-powered vehicles, check out the guide: Performance Exhaust System: Used Manifolds and Sport Catalysts on the Road. You'll find practical tips on selecting used exhaust components for popular brands, including Mercedes.

If you are planning a comprehensive repair or upgrade of the engine area in your Mercedes and need other parts from the same group, such as additional manifolds, connecting sections, or joining elements, check the available parts in the Mercedes Exhaust Manifolds category.