This workshop service repair manual provides comprehensive information for the Iveco N40 ENT M25 NEF engine, a robust internal combustion engine designed for automotive service and repair. Engineered for reliability and performance, the N40 ENT M25 NEF engine represents a significant advancement in its class. This manual details special aspects of the product and proprietary component instructions, ensuring that users can effectively understand and manage this advanced engine system. The purpose of this English-language manual is to guide owners, mechanics, and technicians through routine maintenance, diagnostic procedures, and repair processes. It covers a wide range of topics including tune-ups, servicing, removal and installation, assemblies and disassemblies, and specific systems such as fuel, ignition, lubrication, exhaust, and electrical. Safety precautions and the use of specialized tools, identified by Iveco N40 ENT M25 NEF engine special tool numbers, are also emphasized to ensure proper and safe operation.