The BMW 3 Series (E46) represents a significant chapter in the history of premium compact executive vehicles, produced from 1998 to 2006. Available in Sedan, Coupe, Convertible, and Sport Wagon (Touring) body styles, the E46 lineup, including models such as the 323i, 325i, 328i, 330i, and the high-performance M3, is renowned for its exceptional driving dynamics, sophisticated engineering, and robust build quality. Its appeal lies in a blend of sportiness and luxury, making it a highly regarded choice for discerning drivers and a platform that has garnered numerous accolades, including frequent appearances on 10Best lists and recognition for its advanced powertrains. This comprehensive workshop manual provides detailed guidance for the maintenance, repair, and diagnostics of the BMW 3 Series (E46) models. Covering a vast array of systems from the powertrain, chassis, and electrical components to body and trim, it offers step-by-step procedures for everything from routine oil changes to complex engine rebuilds and electrical troubleshooting. With its in-depth technical information, diagnostic fault finding, and coverage of specific model variants and known issues, this manual serves as an indispensable resource for owners, mechanics, and technicians aiming to preserve the integrity and performance of their E46 vehicle.