🏷️ Basic Information Identification Make: Subaru Model: Impreza WRX STi Year: 2004 Chassis Code: GDB-E (Applicable to later 2004 models, specifically the 'E' generation) Codes Engine Code Primary: EJ257 👋 Introduction Market Position Market Niche: High-performance, rally-bred compact sedan, positioned as a driver's car with AWD capabilities and potent turbocharged engine. Competitive Analysis Key Competitors: Mitsubishi Lancer Evolution, Ford Focus RS, Volkswagen Golf GTI (though the WRX STi is generally positioned higher in performance). Key Features Performance Focus: Emphasis on turbocharged power, Symmetrical All-Wheel Drive, and performance-oriented chassis tuning. Rally Heritage: Direct lineage and technology derived from Subaru's successful World Rally Championship campaigns. 📋 Manual Details Coverage Areas Coverage: Comprehensive service, maintenance, repair, and troubleshooting for the 2004 Subaru Impreza WRX STi. Page Count Page Count: Estimated 2000+ pages (typical for a complete factory service manual of this era and detail level) Manual Type Manual Type: Factory Service Manual (FSM) / Professional Repair Manual Language Language: English Format Format: Digital (likely PDF, as indicated by 'ma......' suggesting a manual file) 📖 Manual Coverage Systems Covered Engine System: Detailed diagnostics, overhaul procedures, component testing, fuel injection, ignition system, emissions control, cooling system, lubrication system. Transmission System: Manual transmission (TY856 6-speed), clutch system, driveline components, differentials (front, center DCCD, rear). Braking System: Hydraulic system, ABS, brake component inspection and replacement (discs, pads, calipers), bleeding procedures. Suspension System Suspension Coverage: Front and rear suspension geometry, strut assembly, control arms, bushings, alignment specifications, wheel bearing service. Electrical System Electrical Coverage: Wiring diagrams, component locations, fuse and relay identification, diagnostic trouble codes (DTCs), ECU functions, lighting, power accessories. Body And Chassis Body Chassis Coverage: Body panel removal and installation, interior trim, exterior lighting, chassis lubrication, frame specifications. Hvac System HVAC Coverage: Air conditioning system diagnosis, refrigerant handling, heater core, climate control unit. Fuel System Fuel System Coverage: Fuel pump, injectors, fuel pressure regulator, evaporative emission control (EVAP). Procedures Included Scheduled Maintenance: Oil changes, filter replacements, spark plug replacement, fluid flushes, belt inspections and replacements. Troubleshooting: Diagnostic flowcharts, symptom-based troubleshooting, common fault identification. Engine Rebuild: Detailed disassembly, inspection, repair, and reassembly of the EJ257 engine, including torque specifications for all critical fasteners. Transmission Overhaul: Complete teardown, inspection, and reassembly of the TY856 6-speed manual gearbox. Drivetrain Service: CV axle replacement, driveshaft inspection, differential fluid changes, DCCD (Driver's Control Center Differential) system service. Brake Service: Brake pad and rotor replacement, caliper overhaul, brake line replacement, ABS bleeding. Suspension And Steering: Strut replacement, ball joint service, tie rod end replacement, power steering system diagnosis. Electrical Diagnostics: Wiring harness repair, sensor testing, actuator testing, ECM/PCM troubleshooting. Technical Depth Depth Level: Expert; covers from basic maintenance to complete engine and transmission rebuilds, including advanced diagnostics and component-level repair. 📊 Manual Specifications File Format Digital Format: PDF (Searchable text is highly probable for a professional manual) Print Quality Print Quality Suitability: Suitable for professional printing or digital viewing; contains detailed diagrams and schematics. Binding Type Binding Type: N/A (Digital format) Paper Type Paper Type: N/A (Digital format) ⚙️ Engine Specifications Primary Engine Engine Type: 2.5-liter, DOHC, turbocharged, intercooled horizontally opposed flat-four (Boxer engine) Performance Horsepower: 300 bhp @ 6000 rpm (approximate, often rated slightly higher in real-world dyno tests for the STi variant) Torque: 300 lb-ft @ 4000 rpm (approximate, often rated slightly higher in real-world dyno tests for the STi variant) Fuel System Fuel Injection: Multi-point fuel injection with Denso top-feed 650cc injectors. Engine Features Internals: Forged pistons and connecting rods, sodium-filled exhaust valves, reinforced crankshaft. Cooling System Radiator Type: High-performance aluminum radiator, often requiring specific Subaru coolant. Lubrication Oil Type And Capacity: SAE 5W-30 synthetic oil recommended, approximately 5.8 quarts (5.5 liters) capacity with filter. Check manual for exact specification. 🔧 Transmission Standard Transmission Type: 6-speed manual transmission (TY856) Optional Optional Transmissions: None (STi models were exclusively manual) Features Dccd: Driver's Control Center Differential (DCCD) allowing manual adjustment of front/rear torque split, or automatic mode. Fluid Specifications Transmission Fluid: Manual transmission fluid (MTF) for the gearbox and front differential, typically 75W-90 GL-5. Rear differential fluid 75W-90 GL-5. Refer to manual for exact Subaru specifications and capacities. 📐 Dimensions Exterior Length: 4,405 mm (173.4 in) Width: 1,740 mm (68.5 in) Height: 1,425 mm (56.1 in) Wheelbase: 2,625 mm (103.3 in) Weights Curb Weight: Approx. 1,440 kg (3,175 lbs) Cargo Trunk Volume: Approx. 0.326 m³ (11.5 cu ft) 🛡️ Safety Features Ratings NHTSA Ratings: Likely achieved good ratings for its time, but specific NHTSA ratings for the 2004 WRX STi may vary. Refer to official archives for precise data. Active Features AWD System: Subaru Symmetrical All-Wheel Drive with DCCD and viscous center differential. ABS: Standard Anti-lock Braking System. Passive Features Airbags: Front driver and passenger airbags, potentially side airbags depending on trim. Body Structure: Reinforced chassis and crumple zones. 💡 Technology Features Infotainment Head Unit: Standard AM/FM/CD player with potential for...