BMW E81 E87 E90 118i 318i N43 Complete Engine N43B20AY with 10k miles

BMW E81 E87 E90 118i 318i N43 Complete Engine N43B20AY with 10k miles designed for BMW 1 Series E81/E87 118i and 3 Series E90 318i models is an attractive solution for drivers looking for a factory powertrain with low mileage. With a mileage of approximately 95,000 km, this unit offers a reasonable compromise between durability and purchase cost, while maintaining the refinement and dynamics characteristic of BMW. It is a perfect choice for those who want to restore their car to full performance while maintaining the original engine specification from the N43 family.

Specifications and technical data

• SKU: 0427103-5
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 0427103
• Substitutable numbers: 11000427103, 0427103, 11000427104, 0427104, 116i316i122HP, N43B20A, N43, N43B20
• Category: Engines
• Mileage: 59 000

Purpose and compatibility

The offered engine belongs to the Engines category and is structurally matched to the petrol versions of the BMW 118i E81/E87 and 318i E90 with the N43 unit. It is a complete powertrain that allows for a technically correct replacement of a damaged engine with an original unit from the same family, without the need for costly mechanical or electrical modifications.

The N43B20AY unit is a more modern design from the N43 family, engineered for efficient combustion and decent flexibility in daily driving. Using an engine from the same generation ensures compatibility with factory equipment, the ECU, and the vehicle's wiring, which facilitates the installation process and subsequent diagnostics.

Technical characteristics of the N43B20AY unit

The N43B20AY engine is a four-cylinder, inline petrol unit from the N43 family, used in compact and mid-size BMW models. The design is based on a lightweight block and cylinder head with an advanced valve control system, which allows for a favorable combination of performance and moderate fuel consumption. The version used in the 118i and 318i provides smooth power delivery, good throttle response, and the refinement typical of modern BMW engines.

For workshops and users, it is important that this unit is widely covered in BMW service documentation, which facilitates maintenance, adjustments, and potential service repairs. As a result, the N43B20AY engine is predictable in terms of service, and the availability of technical information and service parts remains at a good level.

Benefits of choosing a used BMW engine

Purchasing a used engine from the N43 family for a BMW 118i or 318i significantly reduces repair costs compared to a brand-new unit, while maintaining the manufacturer's original specifications. Low mileage combined with its factory origin makes it an attractive solution for both private users and professional workshops specializing in the BMW brand.

To better understand the differences between new and used powertrains, selection procedures by OEM numbers, and real cost proportions, it is worth reading our expert guide: Why it is worth buying used gearboxes and engines – facts instead of myths. The article helps you approach the purchase of a used engine consciously and verify the profitability of such an investment.

Practical installation and operating tips

Before installation, standard preparatory steps typical for used power units are recommended, such as checking for leaks, verifying the condition of accessories, changing oil and filters, and replacing service items according to the manufacturer's recommendations. This approach minimizes the risk of unplanned downtime and allows you to fully utilize the potential of the purchased engine.

It is also worth ensuring proper adaptation of the engine control unit and checking operating parameters after installation using appropriate diagnostic software. This allows for quick detection of any irregularities and ensures stable, safe operation of the unit in daily use.

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 components from the same group, such as additional power units, engine blocks, or complete powertrains, check out the available parts in the BMW Engines category.

When planning larger investments in the drivetrain and a long-term strategy for maintaining the car's value, our guide on the impact of original used components on the vehicle's resale price may also be helpful: original used parts and the car's resale price. This makes it easier to choose service solutions that are beneficial both technically and financially.