BMW E90 320si N45 173HP Complete Engine N45B20A New Timing Installed WARRANTY

Warranty and technical condition of the part

The engine is sold with a 90-day warranty.

The warranty covers the engine itself; engine accessories are covered by a 30-day warranty.

The power unit was tested before removal and is in full working order.

Listing details

The offer applies to a complete engine.

The engine comes from a right-hand drive (RHD) vehicle. The wiring harness is not compatible with left-hand drive (LHD) vehicles and requires replacement or modification.

BMW E90 320si N45 173HP Complete Engine N45B20A New Timing Installed WARRANTY is a specialized power unit from the N45 family, prepared for demanding users of the 3 Series E90. This complete four-cylinder petrol engine with a freshly installed timing system provides a solid foundation for professional repair or replacement of the unit in a BMW vehicle. It is a solution for drivers who expect precise engine performance and stable operating parameters.

Specifications and technical data

• SKU: 0404479-3
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 0404479
• Substitutable numbers: 11000404479, 0404479, 11000404480, 0404480
• Fuel type: Petrol
• Number of cylinders: 4
• Category: Engines
• Mileage: 59 000

Technical characteristics of the N45B20A engine

The N45B20A series engine is a four-cylinder, inline petrol unit designed for dynamic performance in the BMW E90 320si model. The four-cylinder construction promotes smooth operation, while the use of petrol fuel allows for quick throttle response and precise power delivery. The unit was developed with higher operating speeds in mind, which is characteristic of the 320si version, geared towards more sporty use.

A key advantage of this specific unit is the new timing system, which significantly increases operational safety and reduces the risk of costly failures in the valve timing area. The complete nature of the unit facilitates installation in place of the old engine, minimizing the need to transfer a large number of auxiliary components.

Purpose and application in the BMW E90 320si

The offered engine has been configured for installation in the BMW 3 Series E90 in the 320si version, where precision handling, quick revving, and stable performance across the entire RPM range are essential. The four-cylinder petrol unit fits well with the character of the car's light, balanced front end, which helps maintain proper vehicle geometry and balance.

The engine will work well both as a replacement in the event of damage to the existing unit and for restoration projects where maintaining the original 320si specification is important. Thanks to its completeness and new timing, it serves as a favorable base for further configuration of accessories according to the requirements of a specific vehicle.

Benefits of installing a complete petrol engine

Choosing a complete petrol engine from the N45 family brings a number of practical service and operational benefits:

• reduced vehicle downtime due to the ability to replace the entire unit more quickly,
• maintenance of structural consistency with the factory configuration of the BMW E90 320si,
• easier diagnostics after installation thanks to a known, uniform engine platform,
• lower risk of timing synchronization issues due to its fresh replacement.

Additionally, a used engine with a new timing system allows for optimizing the cost-to-durability ratio – a key, critical area has already been refreshed, which in practice translates into greater peace of mind during further operation.

Selection by OEM numbers and practical tips

When selecting a power unit for a specific BMW vehicle, it is extremely important to verify compatibility using OEM numbers and interchangeable part numbers, as well as vehicle data (VIN). This helps avoid problems with the compatibility of accessories, the engine control unit, or the electrical installation. In case of doubt, it is worth using professional support when matching the unit to the specific car configuration.

To better understand how to safely choose used power units and what to look for when purchasing, the following expert guide will be helpful: Why it is worth buying used gearboxes and engines – facts instead of myths. There you will find a discussion of selection procedures by VIN and OEM, as well as practical examples of cost calculations.

BMW engines – expansion and modernization of the powertrain zone

If you are planning a comprehensive repair or modernization of the engine area in your BMW and need other elements from the same group, such as blocks, cylinder heads, or complete power units, check the available parts in the BMW Engines category.

For users who want to deepen their knowledge about the advantages of original components, a valuable supplement will be the article Quality guarantee and OEM safety – why used original car parts are the best choice for your car?, describing the importance of original components in the context of safety and long-term operating costs.