This supplemental workshop service manual provides in-depth technical information for the 2002 Subaru Impreza WRX STI, chassis code GDB, featuring the EJ207 engine. Building on Subaru's renowned rally heritage, this performance-oriented compact sedan is distinguished by its horizontally-opposed twin-scroll turbocharged engine, Symmetrical All-Wheel Drive with Driver Controlled Center Differential (DCCD), STI-tuned suspension, and Brembo braking system. Engineered for enthusiasts and performance driving, the WRX STI of this second generation (GD/GG) offered a compelling blend of on-road capability and track-ready prowess, making it a significant competitor in its segment.

This manual is designed to supplement existing workshop resources, offering detailed coverage of the WRX STI's unique systems and high-performance components. It encompasses specific procedures for maintenance, repair, and diagnostics related to the EJ207 engine, including its turbocharging and intercooling systems, the 6-speed manual transmission with DCCD, advanced suspension and braking setups, and STI-specific body and interior modifications. With comprehensive technical data, troubleshooting guides, and explanations of specialized procedures, this manual serves as an essential reference for owners, mechanics, and technicians aiming to maintain, diagnose, and repair the 2002 Subaru Impreza WRX STI.