🏷️ Basic Information Identification Make: Subaru Model: Impreza WRX STI Year: 2004 Codes Chassis Code: GDB Engine Code Primary: EJ257 Trim Level: STI 👋 Introduction Market Position Positioning: Performance sedan/coupe, rally-bred homologation special, enthusiast vehicle. Competitive Analysis Competitors: Mitsubishi Lancer Evolution, Subaru WRX (non-STI variants), Ford Focus RS, VW Golf R. Key Features Performance Focus: Turbocharged Boxer engine, Symmetrical All-Wheel Drive, advanced differential systems. Driving Dynamics: Legendary handling, driver-focused cockpit, responsive steering. Manual Value Target Audience: Enthusiast owners, independent repair shops, performance tuners. Distinctiveness: Provides dealership-level technical data not typically available to the public. 📋 Manual Details Coverage Areas Primary Coverage: Vehicle Service and Repair Secondary Coverage: Diagnostics, Troubleshooting, Maintenance, Overhaul Page Count Estimated Pages: 2000+ Manual Type Type: Factory Service Manual / Workshop Manual Language Language: English Format Format: PDF 📖 Manual Coverage Systems Covered Engine Mechanical: Complete overhaul, component replacement (pistons, rods, crankshaft, valves, camshafts), timing belt/chain system, lubrication system, cooling system. Engine Management: ECU diagnostics, fuel injection system, ignition system, emission control systems (catalytic converter, EGR, secondary air injection), sensors and actuators. Transmission Manual: Driveshaft, differential, gearbox overhaul, clutch replacement, shift linkage. Transmission Automatic: Not applicable for this STI model. Drivetrain AWD: Center differential, viscous coupling, rear differential, hub assemblies, CV joints. Suspension: Front and rear suspension components (struts, springs, control arms, bushings, sway bars), alignment specifications. Brakes: Brake system hydraulics, ABS system, rotor and pad replacement, caliper overhaul, brake bleeding procedures. Steering: Power steering system, steering rack, tie rods, wheel alignment. Electrical System: Battery, charging system, starting system, lighting, instrumentation, power windows, locks, HVAC controls, audio system. Body And Interior: Body panel removal and installation, door mechanisms, interior trim, seats, dashboard components, glass replacement. HVAC: Air conditioning system, heating system, blower motor, climate controls, refrigerant handling. Procedures Included Maintenance: Oil changes, filter replacements, spark plug replacement, fluid checks and changes, brake inspections. Troubleshooting: Diagnostic flowcharts for common issues, symptom-based problem diagnosis. Repair: Step-by-step instructions for component replacement, system repair, and adjustments. Diagnostics: OBD-II diagnostic trouble codes (DTCs), sensor data interpretation, scan tool usage. Rebuilds: Detailed procedures for engine and transmission rebuilding, including torque specifications and clearances. Wiring Diagrams: Comprehensive electrical schematics for all vehicle systems. Technical Depth Depth: Expert level, suitable for professional technicians and advanced DIY enthusiasts. Scope: Full vehicle service and repair, from routine maintenance to complete engine rebuilds. 📊 Manual Specifications File Format Format: PDF Searchability: Searchable text content Printability: Printable pages Print Quality Quality: High-resolution scans for clear text and diagrams Binding Type Binding: N/A (Digital PDF) Paper Type Paper Type: N/A (Digital PDF) ⚙️ Engine Specifications Primary Engine Engine Type: Horizontally Opposed Turbocharged (Boxer) Displacement: 2.5 Liters (2457 cc) Engine Code: EJ257 Performance Horsepower Est: 300 hp @ 6000 rpm (SAE Net) Torque Est: 300 lb-ft @ 4000 rpm (SAE Net) Fuel System Fuel Delivery: Multi-point Fuel Injection (MPI), Electronic Throttle Control (ETC) Turbocharger: IHI VF30 (or similar depending on market), Intercooled Engine Components Cylinder Head: Dual Overhead Camshaft (DOHC), 16 valves Compression Ratio: 8.0:1 Fluid Specifications Oil Type: SAE 5W-30 Synthetic (API SG or SH) Oil Capacity: 4.5 US quarts (4.3 L) with filter Coolant Type: Subaru Super Coolant (Blue) 🔧 Transmission Standard Transmission Type: 6-Speed Manual Transmission Features Driver Control: Driver Controlled Center Differential (DCCD) with automatic and manual modes. Fluid Type: GL-5 75W-90 Gear Oil (Transmission and Front Differential) Gear Ratios Primary 1St Gear: 3.636 2Nd Gear: 2.063 3Rd Gear: 1.448 4Th Gear: 1.094 5Th Gear: 0.970 6Th Gear: 0.777 Reverse: 3.545 Final Drive: 3.545 Drivetrain Spec AWD System: Symmetrical All-Wheel Drive with DCCD and Helical Front/Limited Slip Rear Differentials. 📐 Dimensions Exterior Length: 173.8 in (4415 mm) Width: 69.7 in (1770 mm) Height: 56.1 in (1425 mm) Wheelbase: 103.0 in (2615 mm) Front Track: 60.0 in (1525 mm) Rear Track: 59.4 in (1510 mm) Weights Curb Weight Est: 3329 lbs (1510 kg) Gross Weight Rating Est: 4343 lbs (1970 kg) Wheel And Tire Wheel Size: 17 x 8.0 inches Bolt Pattern: 5 x 100 mm Tire Size Std: 225/45R17 Fuel Capacity Fuel Tank Capacity: 15.6 US gallons (59 L) 🛡️ Safety Features Ratings NHTSA Front Crash Rating: 4/5 Stars (Driver/Passenger) NHTSA Side Impact Rating: 4/5 Stars (Front/Rear Passenger) IIHS Crashworthiness: Good (Frontal Offset) Active Features ABS: Standard Anti-lock Braking System (ABS) with Electronic Brakeforce Distribution (EBD). Traction Control: Standard Traction Control System (TCS) and Vehicle Stability Control (VDC). Passive Features Airbags Front: Driver and front passenger airbags Airbags Side: Optional front side-impact airbags (market dependent) Seatbelts: 3-point seatbelts with pretensioners and load limiters. Body Structure: Reinforced unibody construction with front and rear crumple zones. 💡 Technology Features Infotainment Head Unit: Factory AM/FM/CD player, optional premium audio system. Display: Basic digital display for clock, temperature, and audio information. Driver Assistance Cruise Control: Standard electronic cruise control. Dccd: Driver Controlled Center Differential provides advanced AWD torque management. Connectivity Bluetooth:...