🏷️ Basic Information Identification Make: Subaru Model: Impreza (STI) Model Year: 2006 Codes Chassis Code: GDB (WRX STI) Engine Code Primary: EJ257 👋 Introduction Market Position Positioning: Performance variant of the Subaru Impreza, targeting enthusiasts and those seeking a capable all-wheel-drive rally-bred sedan. Competitive Analysis Competitors: Mitsubishi Lancer Evolution, Volkswagen Golf R, Ford Focus RS (depending on specific market and year comparisons). Key Features Drivetrain: Symmetrical All-Wheel Drive (AWD) system with Driver Controlled Centre Differential (DCCD). Engine Type: Turbocharged Boxer Engine Performance Focus: Tuned for performance, handling, and rally-inspired driving dynamics. 📋 Manual Details Coverage Areas Primary Coverage: Workshop Service Repair Secondary Coverage: Maintenance, Diagnostics, Troubleshooting, Rebuilding, Restoration Page Count Estimated Page Count: Extensive (Full Workshop Manual) Manual Type Type: Digital Workshop Service Repair Manual Language Language: English Format Format: Digital Download (Likely PDF) 📖 Manual Coverage Systems Covered Engine Mechanical: Complete Overhaul & Rebuilding Engine Performance: Detailed coverage, tuning parameters Engine Electrical: Wiring Diagrams, Sensor Diagnosis Transmission: Removal & Installation, In-Car Servicing Brakes: Complete Servicing Procedures, Specifications Suspension: Front End, Alignment Procedures & Specifications Drivetrain: U-Joint and CV-Joint Service Procedures Body Electrical: Sunroofs, Complete Wiring Diagrams Climate Control: Air Conditioning System Servicing Procedures Included Maintenance Schedules: Factory Maintenance Schedules & Charts Timing Belt: Timing Belt Replacement & Service Procedures Diagnostics Troubleshooting: Trouble Codes, Computer Diagnostic Trouble Tree Charts, Troubleshooting & Diagnostics Repair Procedures: Step-by-step instructions for all major repairs Wiring Schematics: Complete Wiring Diagrams Torques: Complete Torque Specifications Technical Depth Depth: Comprehensive: Covers everything from basic maintenance to full engine rebuilding and advanced diagnostics, mirroring professional technician resources. Illustrations Count: Hundreds of Illustrations Diagrams Type: Vacuum Diagrams, Serpentine Belt Routings With Diagrams 📊 Manual Specifications File Format Format: Digital (likely PDF), Printable Print Quality Quality: High-quality, clear text and images Binding Type Binding: Not Applicable (Digital) Paper Type Paper: Not Applicable (Digital) ⚙️ Engine Specifications Primary Engine Engine Type: Horizontally-Opposed (Boxer), Turbocharged, Intercooled Engine Code: EJ257 Displacement: 2.5 Liters (2457 cc) Bore X Stroke: 99.5 mm x 79.0 mm Compression Ratio: 8.4:1 Performance Horsepower Est: 300 hp @ 6000 rpm (SAE Gross, approximate) Torque Est: 300 lb-ft @ 4000 rpm (SAE Gross, approximate) Fuel System Injection Type: Sequential Multi-Port Fuel Injection (MPI) with Electronic Throttle Control (ETC) Fuel Type: Premium Unleaded Gasoline (91 Octane or higher recommended) Cooling Cooling System: Pressurized liquid cooling system with intercooler Lubrication Oil Type Spec: SAE 5W-30 (API SN or higher, ILSAC GF-5 or higher recommended) Timing Timing Mechanism: Timing Belt Driven DOHC (Dual Overhead Camshafts) with Variable Valve Timing (VVT) 🔧 Transmission Standard Type: 6-Speed Manual Transmission Features Dccd: Driver Controlled Centre Differential (DCCD) system for adjustable torque split Fluid Specifications Manual Transmission Fluid: Subaru Extra-S GL5 75W-90 or equivalent high-quality synthetic gear oil 📐 Dimensions Exterior Length Est: 4415 mm (173.8 inches) Width Est: 1770 mm (69.7 inches) Height Est: 1440 mm (56.7 inches) Wheelbase Est: 2625 mm (103.3 inches) Weights Curb Weight Est: 1495 kg (3296 lbs) Gross Vehicle Weight Rating Est: 1910 kg (4210 lbs) Towing Capacity: Not Recommended/Rated 🛡️ Safety Features Ratings NHTSA Front Impact Est: 5-Star NHTSA Side Impact Est: 5-Star IIHS Roof Strength Est: Good Active Features ABS: Anti-lock Braking System (ABS) Traction Control: Traction Control System (TCS) Electronic Stability: Vehicle Dynamics Control (VDC) Passive Features Airbags: Front dual-stage airbags, Front side-impact airbags, Side curtain airbags Seatbelts: 3-point front and rear seatbelts with pretensioners and force limiters Body Structure: Reinforced body structure with crumple zones 💡 Technology Features Infotainment Head Unit: Factory-installed Clarion or Pioneer audio system with CD player and AM/FM radio. Optional subwoofer. Driver Assistance Cruise Control: Standard Connectivity Auxiliary Input: Optional auxiliary audio input jack 🔧 Maintenance Service Intervals Oil Change Interval: Every 3,750 miles or 3 months (severe driving) / 7,500 miles or 6 months (normal driving) - consult manual for specifics Timing Belt Replacement Interval: Every 105,000 miles or 105 months (critical for EJ257) Transmission Fluid Change Interval: Every 30,000 miles or 30 months (severe driving) / 60,000 miles or 60 months (normal driving) - consult manual Fluid Specifications Coolant Type: Subaru Super Coolant (Blue) or equivalent ethylene glycol-based antifreeze Brake Fluid Type: DOT 3 or DOT 4 Power Steering Fluid Type: Subaru Type A or equivalent ATF Known Issues Ej257 Ring Land Failure: Potential for ring land failure in early EJ257 engines due to detonation. Proper tuning and maintenance are crucial. Clutch Wear: High-performance nature can lead to accelerated clutch wear with aggressive driving. Head Gasket Leaks: While less common than in earlier Subarus, can still occur. Regular coolant checks are advisable. 📚 Vehicle History Brand Heritage Brand Focus: Subaru is renowned for its Symmetrical All-Wheel Drive system and horizontally-opposed (Boxer) engine, often associated with rallying and all-weather performance. Model Evolution Generation: Third Generation (2002-2007) Sti Introduction: The STI (Subaru World Rally Team) variant debuted in 2004 for the GD chassis,...