🏷️ Basic Information Identification Make: Subaru Model: Impreza WRX STI Year: 2008 Codes Chassis Code: GR/GV Chassis (for hatchback & sedan respectively) Engine Code Primary: EJ257 Engine Code Secondary: EJ207 (mentioning H4DOTC/H4SO suggests potential for referencing other variants or engine types within the scope of the manual, though EJ257 is specific to STI) 👋 Introduction Market Position Segment: Performance Compact Sedan/Hatchback (Rally-inspired) Competitive Analysis Competitors: Mitsubishi Lancer Evolution, Volkswagen GTI, Mazdaspeed3, Ford Focus RS (though the latter came later). Key Features Performance Focus: Symmetrical All-Wheel Drive, turbocharged boxer engine, performance-tuned suspension, driver-centric interior. Rally Heritage: Direct lineage from Subaru's World Rally Championship (WRC) success. 📋 Manual Details Coverage Areas Main Sections: Body, Body Repair, Chassis, Engine, Transmission, Wiring, STI Specific Body, STI Specific Body Repair, STI Specific Chassis, STI Specific Engine, STI Specific Transmission, STI Specific Wiring Page Count Estimated Pages: Over 2000 (typical for comprehensive service manuals of this era and scope) Manual Type Type: Factory Service Manual / Workshop Repair Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Engine: EJ257 (2.5L DOHC Turbocharged Boxer), Engine mechanical, lubrication system, cooling system, fuel system, ignition system, emission control system, engine management system (ECU), turbocharger system, intercooler system. Transmission: 6-speed manual transmission (TY757), clutch system, drivetrain components (driveshafts, differentials - front, center, rear). Chassis: Suspension (front MacPherson strut, rear double wishbone), steering system, brake system (including Brembo front calipers), wheel and tire specifications, chassis components, body structure. Body: Body construction, exterior panels, interior trim, doors, hood, trunk lid, glass, seals, collision repair procedures, body panel alignment, rust prevention and repair. Electrical: Wiring diagrams (full vehicle), power distribution, lighting, instruments, audio system, HVAC controls, SRS (Airbag) system, ABS, traction control, body control modules, starter and charging system. Procedures Included Maintenance: Scheduled maintenance, oil changes, filter replacements, fluid checks and top-offs, spark plug replacement, belt inspection and replacement, brake service, tire rotation. Repair: Complete engine rebuild procedures, transmission overhaul, suspension component replacement, brake caliper rebuild/replacement, body panel repair and replacement, electrical component diagnosis and repair, HVAC system repair. Troubleshooting: Diagnostic flowcharts, fault code interpretation (DTCs), common problem diagnosis, specific symptom troubleshooting for all major systems. Diagnostics: On-board diagnostics (OBD-II), scan tool usage, live data interpretation, specific component testing procedures, sensor calibration, ECU relearn procedures. Technical Depth Depth: Comprehensive; covers everything from basic fluid checks to complete engine and transmission rebuilds, including detailed diagnostic procedures and wiring diagrams. Suitable for professional technicians and advanced DIY enthusiasts. 📊 Manual Specifications File Format File Type: PDF Searchability: Searchable text content Print Quality Quality: High-resolution scans, clear diagrams and illustrations Binding Type Binding: N/A (Digital Download) Paper Type Paper: N/A (Digital Download) ⚙️ Engine Specifications Primary Engine Type: 2.5L DOHC 16-valve Turbocharged Boxer 4-Cylinder Engine Code: EJ257 Performance Horsepower Est: 305 hp @ 6000 rpm Torque Est: 290 lb-ft @ 4000 rpm Fuel System Injection: Multi-point fuel injection (MPI) with Electronic Throttle Control (ETC) Fuel Type: Premium Unleaded Gasoline (91 octane or higher recommended) Cooling System Coolant Type: Subaru Super Coolant (Blue) or equivalent 50/50 mix with distilled water Lubrication System Oil Type: Synthetic 5W-30 Engine Management ECU Type: Engine Control Unit (ECU) with access to engine parameters for diagnostics and tuning. 🔧 Transmission Standard Type: 6-speed Manual Transmission Transmission Code: TY757 Optional Transmission Type: N/A (STI models exclusively offered with manual) Features Drivetrain: Symmetrical All-Wheel Drive with Driver Controlled Center Differential (DCCD) Differentials: Helical-type limited-slip front differential, mechanical limited-slip rear differential. Fluid Specifications Gear Oil Type: GL-5 Gear Oil (check manual for specific viscosity, e.g., 75W-90) 📐 Dimensions Exterior Wheelbase Hatchback: 2620 mm (103.2 in) Wheelbase Sedan: 2625 mm (103.3 in) Track Width Front: 1530 mm (60.2 in) Track Width Rear: 1540 mm (60.6 in) Weights Curb Weight Hatchback Est: 1505 kg (3318 lbs) Curb Weight Sedan Est: 1495 kg (3296 lbs) 🛡️ Safety Features Ratings NHTSA Front Driver: 5-Star (for the 2008 model year generally, specific STI ratings may vary but are typically high) NHTSA Front Passenger: 5-Star Active Features ABS: Standard Anti-lock Braking System with Electronic Brake-force Distribution (EBD) Traction Control: Standard Traction Control System (TCS) and Vehicle Dynamics Control (VDC) Passive Features Airbags: Front dual-stage airbags, front side-impact airbags, side-curtain airbags (hatchback). Seatbelts: 3-point height-adjustable front seatbelts with pretensioners and force limiters, rear 3-point seatbelts. 💡 Technology Features Infotainment Head Unit: Standard AM/FM/CD stereo system with MP3 playback capability and auxiliary audio input. Optional premium audio systems may be available. Driver Assistance Cruise Control: Standard electronic cruise control Connectivity Aux Input: Standard 3.5mm auxiliary audio input jack Performance Tech Dccd: Driver Controlled Center Differential (DCCD) allows manual adjustment of front-to-rear torque split for optimized traction and handling. Si Drive: Subaru Intelligent Drive (SI-DRIVE) system offering three modes: Intelligent (I), Sport (S), and Sport Sharp (S#), adjusting throttle response, VDC, and DCCD behavior. 🔧 Maintenance Service Intervals Oil Change...