🏷️ Basic Information Identification Make: Subaru Model: Impreza WRX STI Year: 2012 Codes Chassis Code: GVB/GRB (Hatchback), GE/GH (Sedan - though 2012 is primarily hatch focus for WRX STI) Engine Code: EJ257 👋 Introduction Market Position Segment: Performance Compact Sedan/Hatchback (G-segment) Target Audience: Enthusiasts, motorsport participants, performance-oriented drivers, professional mechanics. Competitive Analysis Key Competitors: Mitsubishi Lancer Evolution, Volkswagen Golf GTI/R, Ford Focus RS, BMW M235i (depending on market segment and price point). Key Features Performance Focus: Iconic rally heritage, turbocharged Boxer engine, Symmetrical All-Wheel Drive, performance-tuned suspension. Dccd: Driver Controlled Center Differential for adjustable torque distribution. Chassis Rigidity: Enhanced chassis design for improved handling and responsiveness. 📋 Manual Details Coverage Areas Primary Coverage: All mechanical and electrical systems, bodywork, and diagnostics for the 2012 Subaru Impreza WRX STI. Page Count Estimated Pages: 1500-2000+ (typical for a comprehensive workshop manual of this era and complexity) Manual Type Type: Workshop Service Manual / Repair Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Powertrain: Engine (EJ257), turbocharged system, intercooler, exhaust, fuel system, ignition system, cooling system, lubrication system. Drivetrain: Manual Transmission (TY757/TY856 variants), Center Differential (DCCD), Front Differential, Rear Differential, Axles, Driveshafts. Chassis: Suspension (Front MacPherson Strut, Rear Double Wishbone), Steering System (Hydraulic Power Steering), Brakes (ABS, EBD, High-Performance Calipers), Wheels and Tires. Electrical: Battery, charging system, starter, lighting, ignition, engine control (ECU/ECM), transmission control, Body Control Module (BCM), HVAC controls, audio system, power accessories, driver information system, diagnostic connectors (OBD-II). Body And Interior: Body panels, doors, windows, seats, trim, airbags, seatbelts, HVAC system, interior lighting. Procedures Included Maintenance: Routine maintenance, fluid changes (oil, coolant, brake fluid, transmission fluid, differential fluid), filter replacements, spark plug replacement, belt inspection/replacement. Diagnostics: Troubleshooting guides, diagnostic trouble codes (DTCs), electrical testing, component testing, system diagnostics. Repair: Engine overhaul, transmission repair, suspension component replacement, brake system repair, electrical component repair/replacement, body panel repair. Special Procedures: Turbocharger diagnosis and repair, DCCD system calibration and troubleshooting, AWD system service, alignment procedures, specific torque specifications for critical components. Technical Depth Depth: Comprehensive. Covers basic maintenance, detailed component disassembly/reassembly, advanced diagnostics, wiring diagrams, component specifications, and troubleshooting procedures suitable for professional technicians and experienced DIYers. 📊 Manual Specifications File Format File Type: PDF (Portable Document Format) Searchability: Likely text-searchable for quick information retrieval, depending on the original scan quality. Print Quality Print Readability: Designed for clear printing with diagrams, schematics, and text. Binding Type Binding: N/A (Digital Download) Paper Type Paper Quality: N/A (Digital Download) ⚙️ Engine Specifications Primary Engine Engine Type: Horizontally-opposed (Boxer) 4-cylinder, turbocharged and 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 Valve Train: DOHC, 16 valves (4 per cylinder) Performance Horsepower: 305 hp @ 6000 rpm (SAE Net) Torque: 290 lb-ft @ 4000 rpm (SAE Net) Fuel System Fuel Delivery: Sequential multi-port fuel injection (MFI) Fuel Type: Premium Unleaded Gasoline (91 octane or higher recommended) Turbo System Turbocharger Type: Twin-scroll IHI VF52 (or similar based on market) Intercooler: Top-mounted air-to-air intercooler 🔧 Transmission Standard Transmission Type: 6-speed manual transmission Transmission Codes: TY757 (likely variant for GVB/GRB chassis) Features Dccd: Driver Controlled Center Differential with Auto mode. AWD System: Symmetrical All-Wheel Drive with front and rear limited-slip differentials (LSD). Fluid Specs Manual Transmission Fluid: Subaru Extra-S Gear Oil (or equivalent API GL-5 75W-90 synthetic) 📐 Dimensions Exterior Length: Approx. 4,415 mm (173.8 in) Width: Approx. 1,800 mm (70.9 in) Height: Approx. 1,475 mm (58.1 in) Wheelbase: Approx. 2,650 mm (104.3 in) Weights Curb Weight: Approx. 1,505 kg (3,318 lbs) for Hatchback Wheels Tires Wheel Size: 18 x 8.5 inch Tire Size: 245/40R18 Bolt Pattern: 5 x 114.3 mm 🛡️ Safety Features Ratings NHTSA Rating: Not specifically tested as a distinct WRX STI model by NHTSA for 2012, but the base Impreza received 5-star ratings in many categories. IIHS Rating: Similar to NHTSA, specific STI ratings are less common; base Impreza performed well. 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). AWD: Symmetrical All-Wheel Drive provides enhanced traction and stability. Passive Features Airbags: Front airbags, front side-impact airbags, side curtain airbags. Seatbelts: Three-point height-adjustable front seatbelts with pretensioners and force limiters. Chassis Structure: Ring-shaped reinforcement frame. 💡 Technology Features Infotainment Head Unit: Typically a 6-speaker audio system with CD player, MP3 compatibility, SiriusXM Satellite Radio, Bluetooth connectivity, and auxiliary input. Display: Multi-function display in the center console or instrument cluster showing vehicle status and settings. Driver Assistance Cruise Control: Standard electronic cruise control. Keyless Entry: Standard keyless entry and push-button start (depending on trim). Connectivity Bluetooth: Bluetooth hands-free calling and audio streaming. Usb Aux Ports: Auxiliary audio input jack, potential USB port for device charging/audio (depending on market/trim). 🔧 Maintenance Service Intervals Oil Change: Every 3,000-5,000 miles...