BMW E90 E91 E92 LCI Air Intake Hose Filtered Air Pipe Line N57 Diesel 7806371

The BMW E90/E91/E92 LCI N57 Air Intake Duct is a component of the air supply system in diesel engines, responsible for the stable and airtight delivery of filtered air to the power unit. Thanks to its design, tailored to the engine bay architecture of the facelifted BMW 3 Series with the N57 engine, this used duct ensures factory air flow routing and proper cooperation with the filter housing and other intake components.

Specifications and technical data

• SKU: 7806371-1
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 7806371
• Substitutable numbers: 13717806371, 7806371
• Fuel type: Diesel
• Category: Hoses, Lines & Pipes

Purpose and Function in the Intake System

The intake duct in the N57 diesel engine is responsible for the controlled flow of purified air between the filter and the further part of the intake system. A correctly selected component minimizes pressure drops, reduces turbulence, and supports stable turbocharging operation, which translates to smoother engine operation and consistent performance parameters.

In case of leaks or damage to the duct, disturbances in sensor readings, power loss, or unstable engine operation may occur. Using an original, used component from the same model platform ensures geometric compatibility with the factory system and avoids fitting issues.

Benefits of Using an Original Air Intake Duct

Choosing an air intake duct designed specifically for the BMW 3 Series with the N57 engine offers a number of practical advantages:

• maintaining the factory air routing within the engine bay,
• proper fit with the air filter housing and subsequent intake components,
• reducing the risk of leaks at connections thanks to precisely fitted ends,
• maintaining stable operating conditions for the diesel engine,
• easier diagnostics and servicing due to compliance with manufacturer documentation.

For workshops and individual users, this means hassle-free installation and predictable intake system behavior after component replacement.

Application in the N57 Diesel Engine

Diesel engines require a precisely designed intake system to maintain the correct air-to-fuel ratio across a wide range of loads. The intake duct dedicated to the N57 unit supports:

• stable filtered air supply under variable boost,
• proper cooperation with the diesel engine control system,
• maintaining correct combustion parameters across the entire RPM range.

This ensures the air supply system remains consistent with the factory design, which is particularly important in modern diesel units that are sensitive to any leaks and changes in intake geometry.

Condition, Fitment, and Installation

The offered component belongs to the Ducts, Hoses, and Pipes group and is intended for reinstallation in compatible facelifted BMW 3 Series models with the N57 engine. A used duct offers a cost-effective solution while maintaining original construction, facilitating installation in place of a damaged or worn component without the need for system modifications.

For correct selection, it is recommended to verify compatibility by OEM number or by comparing with the currently installed duct, which helps avoid errors and ensures reliable fitment for the specific vehicle configuration.

Complementary BMW Intake System Components

If you are planning a comprehensive repair or upgrade of the engine area in your BMW and need other components from the same group, such as additional intake ducts, flexible hoses, or air guiding pipes, check the available parts in the BMW Ducts, Hoses, and Pipes category.

When selecting used intake system components, it is advisable to follow proven selection and verification procedures. Practical tips for safely purchasing second-hand parts can be found in the guide Safe Purchase of Used Car Parts Online – A Step-by-Step Guide, which covers, among other things, selection by OEM numbers and technical specifications.