🏷️ Basic Information

Make:

Subaru

Model:

Impreza WRX STI

Year:

2012

Chassis Code:

GVB (Hatchback), GRB (Hatchback - previous generation, but often included in discussions)

Engine Code:

EJ257

👋 Introduction

Market Position:

The 2012 Subaru Impreza WRX STI is a highly regarded performance compact sedan/hatchback, positioned as a rally-inspired homologation special and a driver-focused sports car, appealing to enthusiasts seeking all-wheel-drive capability and turbocharged power.

Competitive Analysis:

Competes with other performance compacts like the Mitsubishi Lancer Evolution (though the Evo X production ended shortly after), Volkswagen Golf GTI/R, Ford Focus RS, and other hot hatches and performance sedans. Its unique selling proposition remains its standard Symmetrical All-Wheel Drive system and rally heritage.

Key Features:

2.5-liter turbocharged Boxer engine, Symmetrical All-Wheel Drive, performance-tuned suspension, Brembo brakes, driver-adjustable Vehicle Dynamics Control (VDC) and DCCD (Driver Controlled Center Differential), aggressive styling, and a focus on driver engagement.

📋 Manual Details

Coverage Areas:

Full vehicle service and repair

Page Count:

Likely over 2000 pages (typical for comprehensive factory-level service manuals)

Manual Type:

Workshop Service Repair Manual

Language:

English

Format:

Digital (PDF)

📖 Manual Coverage

Systems Covered:

Engine mechanical, Engine management (ECU, sensors, actuators), Fuel system, Ignition system, Lubrication system, Cooling system, Exhaust system, Turbocharger system, Transmission (manual & automatic), Drivetrain (AWD, differentials, axles), Brakes (ABS, EBD, VDC), Suspension (front & rear), Steering, Electrical system (wiring diagrams, components), Climate control, Body & interior, Body electrical, Diagnostic procedures, Troubleshooting guides, Specifications, Torque values, Maintenance schedules, Emissions control

Procedures Included:

Routine maintenance, Scheduled servicing, Engine overhaul, Transmission repair, Brake system bleeding and component replacement, Suspension component replacement, Steering system diagnostics, Electrical system troubleshooting, Body panel repair, Interior trim removal and installation, Diagnostic trouble code (DTC) interpretation and resolution, Component testing and replacement, Turbocharger assembly/disassembly, Differential and AWD system servicing

Technical Depth:

Comprehensive from basic maintenance to full engine and transmission rebuilds. Includes detailed diagnostic procedures, wiring schematics, and component specifications for professional-level repairs.

📊 Manual Specifications

File Format:

Searchable PDF

Print Quality:

High-resolution scans with clear text and diagrams

Binding Type:

N/A (Digital format)

Paper Type:

N/A (Digital format)

⚙️ Engine Specifications

Engine Type:

2.5L DOHC 16-valve turbocharged horizontally-opposed (Boxer) 4-cylinder

Engine Code:

EJ257

Horsepower:

305 hp @ 6000 rpm

Torque:

290 lb-ft @ 2500 rpm (approx.)

Fuel Induction:

Multi-point fuel injection (MPI) with Sequential Turbo

Fuel Type:

Premium Unleaded Gasoline (91 octane or higher recommended)

ECU Type:

Subaru Select Monitor (SSM) compatible ECU

🔧 Transmission

Transmission Type:

6-speed manual transmission

Transmission Type:

N/A (No automatic option for STI in 2012)

Dccd System:

Driver Controlled Center Differential (DCCD) with Auto/Manual modes

AWD System:

Symmetrical All-Wheel Drive with front helical LSD and rear Torsen LSD

📐 Dimensions

Wheelbase:

103.3 inches (2624 mm)

Length:

179.4 inches (4557 mm) (Hatchback)

Width:

70.7 inches (1796 mm)

Height:

58.1 inches (1476 mm) (Hatchback)

Curb Weight:

Approximately 3350-3400 lbs (1520-1542 kg)

Gross Vehicle Weight Rating:

Not explicitly specified in typical consumer data, but available in detailed service manuals.

🛡️ Safety Features

NHTSA Front Crash Rating:

4 stars

IIHS Top Safety Pick:

Yes (for its model year)

Active Safety Features:

Vehicle Dynamics Control (VDC) with Sport Mode, Traction Control System (TCS), Anti-lock Braking System (ABS), Electronic Brake-force Distribution (EBD), Subaru's Symmetrical All-Wheel Drive

Passive Safety Features:

Front dual-stage airbags, front side-impact airbags, front and rear side-curtain airbags, driver's knee airbag, front seatbelt pre-tensioners and load limiters, adjustable front head restraints, LATCH child seat anchors, Whiplash Protection System.

💡 Technology Features

Infotainment System:

Standard Subaru audio system with CD player, MP3 capability, auxiliary input, and available navigation system with touchscreen interface and Bluetooth connectivity.

Driver Assistance Features:

Limited by modern standards. Primarily features like VDC, TCS, ABS, EBD. No adaptive cruise control or lane keeping assist.

Connectivity Features:

Bluetooth hands-free calling and audio streaming (with compatible head units), USB/iPod integration.

Performance Enhancements:

SI-Drive (Subaru Intelligent Drive) with three modes (Intelligent, Sport, Sport Sharp), DCCD for manual control of the center differential bias, Multi-Mode Driver Controlled Center Differential (DCCD).

🔧 Maintenance

Oil Change Interval:

Every 3,750 miles (6,000 km) or 6 months, whichever comes first (especially under spirited driving conditions).

Major Service Interval:

Refer to manual for specific interval for timing belt (if applicable, though this engine typically uses a timing chain), spark plugs, transmission fluid, differential fluid, brake fluid, coolant.

Engine Oil Type:

5W-30 Synthetic (API SN or newer, ILSAC GF-5 or newer) - Consult manual for specific STI recommendations

Coolant Type:

Subaru Super Coolant (Blue) or equivalent

Transmission Fluid Type:

GL-5 75W-90 Synthetic Gear Oil (for manual transmission)

Differential Fluid Type:

GL-5 75W-90 Synthetic Gear Oil (for front and rear differentials)

Brake Fluid Type:

DOT 3 or DOT 4

Common Issues Engine:

Head gasket failures (less common on EJ257 than older EJ25s, but still a potential issue), piston ring land failures (especially if tuned aggressively without proper supporting modifications), turbocharger failure, oil consumption.

Common Issues Drivetrain:

Clutch wear (especially with aggressive driving), gearbox synchro wear, rear differential issues (less common but possible with hard use).

Common Issues Suspension:

Worn bushings (control arms, sway bars), strut wear, premature wheel bearing failure in some cases.

📚 Vehicle History

Brand Heritage:

Subaru's motorsport heritage, particularly in the World Rally Championship (WRC) with the Impreza, is central to the WRX and WRX STI's identity. The STI (Subaru Tecnica International) division signifies Subaru's high-performance tuning branch.

Model Evolution Context:

The 2012 model is part of the third generation Impreza WRX STI (GE/GH/GR/GV chassis), often referred to as the 'widebody' generation. It marked a refinement of the platform following the significant chassis redesign that introduced the hatchback and adopted the more aggressive styling and wider fenders characteristic of performance variants.

Production Location:

Gunma Plant, Japan

Production Years For This Generation:

2008-2014 (with significant updates in 2011)

🏆 Awards & Recognition

Motorsport Recognition:

The WRX STI lineage is deeply rooted in rally success, including multiple WRC manufacturer and driver championships. The 2012 model carries this prestigious racing pedigree.

Car And Driver Comparison:

Consistently featured in '10Best' lists or comparisons by automotive publications for its performance and handling.

Emissions Certification:

EPA/CARB compliant for its model year.