🏷️ Basic Information Identification Make: Subaru Model: Impreza WRX STI Model Variant: STI (Turbo) / Impreza (Non-Turbo) Year: 2005 Codes Chassis Code: GDB (Impreza chassis) Engine Code Sti: EJ257 Engine Code Non Turbo: EJ204 (commonly found on non-STI Imprezas of this era) 👋 Introduction Market Position Segment: Performance Compact Sedan/Hatchback Usp: Iconic rally heritage, turbocharged performance (STI), symmetrical all-wheel-drive, driver-focused cockpit. Competitive Analysis Competitors: Mitsubishi Lancer Evolution, Honda Civic Si, Volkswagen GTI, Ford Focus SVT. Key Features Performance Focus: Emphasizes track-capable performance and engaging driving dynamics, particularly in the STI variant. AWD Capability: Subaru's renowned Symmetrical All-Wheel Drive system provides superior traction and stability in various conditions. Durability: Known for robust engineering and durability, especially in the boxer engine and AWD drivetrain. 📋 Manual Details Coverage Areas Coverage Scope: All models and all repairs A-Z for 2005 Subaru Impreza WRX STI and non-turbo Impreza variants. Page Count Estimated Page Count: Approximately 2000+ pages (typical for full factory service manuals of this scope). Manual Type Type: Factory Service Manual / Workshop Manual Language Language: English Format Format: Digital (likely PDF, often with searchable text and high-resolution diagrams) 📖 Manual Coverage Systems Covered Engine Mechanical: Engine assembly, disassembly, torque specifications, cylinder head, crankshaft, pistons, connecting rods, valve train, timing belt/chain, lubrication system, cooling system. Engine Management: Fuel injection system, ignition system, emission control systems (catalytic converter, EVAP), engine control unit (ECU) diagnosis, sensors and actuators, turbocharger system (STI). Transmission Manual: Clutch system, gearbox assembly, disassembly, internal components, gear ratios, shifting mechanisms, driveshafts, differentials. Transmission Automatic: If applicable to specific 2005 Impreza models covered, this would include gearbox assembly, hydraulics, torque converter, electronic controls. Drivetrain: All-Wheel Drive (AWD) system, viscous coupling, differentials (front, center, rear), hubs, wheel bearings. Suspension: Front suspension (struts, control arms, bushings), rear suspension (multi-link design), springs, shock absorbers, sway bars, alignment specifications. Steering: Power steering system, steering column, rack and pinion, tie rods, steering knuckle. Brakes: Hydraulic brake system, brake calipers, rotors, pads, master cylinder, brake booster, ABS system, parking brake. Electrical System: Battery, alternator, starter motor, lighting systems (headlights, taillights, interior), fuses, relays, wiring diagrams. Body Exterior: Body panel removal and installation, doors, hood, trunk lid, bumpers, glass, seals, trim. Body Interior: Dashboard, seats, upholstery, HVAC system components, interior trim, audio system, airbags. HVAC: Heating, ventilation, and air conditioning system components, refrigerant handling, diagnosis. Procedures Included Routine Maintenance: Oil changes, filter replacements, fluid checks and top-offs, spark plug replacement, brake fluid flush, coolant flush. Troubleshooting: Diagnostic procedures for common drivability issues, electrical faults, component failures, including specific symptom-based troubleshooting trees. Component Replacement: Step-by-step instructions for replacing major and minor components across all vehicle systems. Rebuild Procedures: Detailed instructions for the complete disassembly, inspection, repair, and reassembly of engine, transmission, and differential components. Wiring Diagrams: Comprehensive electrical wiring diagrams for all major systems, including engine control, body electronics, and lighting. Torque Specifications: Precise torque values for all critical fasteners, essential for proper assembly and preventing damage. Special Tools: Identification and usage of specialized tools required for specific repairs or diagnostics. Tightening Sequences: Specific sequences for tightening critical components such as cylinder heads and wheel nuts. Technical Depth Depth: Comprehensive, covering basic maintenance to complete engine and transmission rebuilds, including advanced diagnostics and troubleshooting. 📊 Manual Specifications File Format File Type: PDF Searchability: Searchable text for quick information retrieval. Image Quality: High-resolution diagrams and images for clarity. Print Quality Print Readability: Designed for clear readability when printed. Binding Type Binding: N/A (Digital Format) Paper Type Paper Quality: N/A (Digital Format) ⚙️ Engine Specifications Primary Engine Sti Engine Type: 2.5L EJ257 Flat-Four (Boxer) Sti Aspiration: Turbocharged and Intercooled Sti Horsepower: Approx. 300 hp @ 6000 rpm (factory rating, often underestimated) Sti Torque: Approx. 300 lb-ft @ 4000 rpm (factory rating) Non Turbo Engine Type: 2.0L EJ204 Flat-Four (Boxer) or similar naturally aspirated variant Non Turbo Aspiration: Naturally Aspirated Non Turbo Horsepower: Approx. 150-170 hp (typical for non-STI models) Non Turbo Torque: Approx. 140-150 lb-ft (typical for non-STI models) Performance Compression Ratio Sti: 8.0:1 Bore X Stroke Sti: 92.0 mm x 91.0 mm Fuel System Fuel Delivery: Multi-point fuel injection (MPI) Fuel Type: Premium Unleaded (91 octane or higher recommended for STI) Engine Components Sti Engine Internals: Forged pistons, stronger connecting rods, sodium-filled exhaust valves (STI specific). 🔧 Transmission Standard Sti Transmission Type: 6-speed manual Optional Non Turbo Transmission Type: 5-speed manual or 4-speed automatic (depending on trim/market) Features AWD System: Symmetrical All-Wheel Drive with Driver Controlled Center Differential (DCCD) on STI models. Fluid Specifications Sti Gearbox Fluid: Subaru ExtraS PS Fluid (or equivalent API GL-5 75W-90 synthetic gear oil) AWD Differential Fluid: Subaru ExtraS PS Fluid (or equivalent API GL-5 75W-90 synthetic gear oil) 📐 Dimensions Exterior Wheelbase: Approx. 103.1 inches (2619 mm) Length: Approx. 174.5 inches (4432 mm) Width: Approx. 69.7 inches (1770 mm) Height: Approx. 57.9 inches (1470 mm)...