The 1990 Audi 90, chassis code Type 85 (B3), represents a sophisticated compact executive sedan known for its advanced engineering and performance-oriented design. As a premium offering, it competed with established luxury marques, distinguishing itself with a unique 2.3L 5-cylinder engine and the highly regarded Quattro all-wheel-drive system. This model emphasized aerodynamic styling, a well-appointed interior, and a focus on driver engagement, embodying Audi's commitment to 'Vorsprung durch Technik'. Its robust construction and technological features, including the Bosch Motronic engine management, contributed to its reputation for quality and reliability.

This comprehensive factory authorized repair manual provides detailed information for the maintenance, repair, and troubleshooting of the 1990 Audi 90. It covers essential systems including the 2.3L 5-cylinder engine (NG engine code), 5-speed manual and 4-speed automatic transmissions, and both Front-Wheel Drive (FWD) and Quattro All-Wheel Drive (AWD) configurations. The manual includes in-depth procedures for engine mechanicals, fuel and ignition systems, drivetrain components, suspension, steering, brakes with ABS, and the electrical system. It is an indispensable resource for owners, mechanics, and technicians seeking to ensure the optimal performance and longevity of their vehicle through detailed technical specifications, diagnostic guidance, and repair instructions.