This manual covers the CX, produced from 1974 to 1991, with specific details relevant to the 1978 model year. The CX, known for its avant-garde design and innovative engineering, succeeded the iconic DS. It featured a unique self-leveling hydropneumatic suspension system, advanced for its time, which contributed to exceptional ride comfort and stability. Engine options included the CX2000 with a 1985cc inline-4 engine, the CX2200 Diesel with a 2175cc inline-4, and the CX2400 with a 2377cc inline-4 engine, offering approximately 99 bhp and 112 bhp respectively. The vehicle's design emphasized aerodynamics and comfort, with dimensions approximately 4.75 meters in length, 1.77 meters in width, and 1.37 meters in height, and a curb weight ranging from 1250-1350 kg. This comprehensive full service repair manual provides detailed guidance for all aspects of repair, maintenance, rebuilding, refurbishment, and restoration for the CX. It covers powertrain, drivetrain, suspension and steering systems, brakes, electrical systems, and body/chassis components. The manual includes systematic diagnostic procedures, detailed wiring diagrams, and step-by-step instructions for component removal, installation, and overhaul, designed for professional technicians and serious DIY mechanics. Key areas include scheduled maintenance, fluid changes, troubleshooting common and complex issues, and rebuilding major components. Illustrations and clear formatting ensure ease of use for maintaining and repairing this technologically advanced vehicle.