🏷️ Basic Information

Make:

Subaru

Model:

Impreza WRX STI

Year:

2011

Chassis Code:

GR/GV

Engine Code:

EJ257

👋 Introduction

Performance Segment:

Compact performance sedan/hatchback, rallying heritage.

Competitors:

Mitsubishi Lancer Evolution, Volkswagen Golf GTI, Ford Focus RS.

Drivetrain:

Symmetrical All-Wheel Drive (AWD) with Driver Controlled Center Differential (DCCD).

Engine:

High-performance turbocharged Boxer engine.

Suspension:

STI-tuned performance suspension, often with inverted struts and thicker sway bars.

Brakes:

Signature Brembo braking system.

📋 Manual Details

Manual Type:

Full Service Repair Manual

Language:

English

Format:

Digital Download (likely PDF)

Estimated Page Count:

1500+

📖 Manual Coverage

Engine Mechanical:

Detailed overhaul procedures for EJ257 engine, including short block, cylinder heads, valvetrain, piston/ring assembly, crankshaft, connecting rods, and timing components.

Engine Management:

Engine control unit (ECU) diagnostics, fuel injection system, ignition system, emission control systems (catalytic converter, EVAP), sensor and actuator testing (MAF, MAP, O2, TPS, CMP, CKP), and throttle body operation.

Transmission:

6-speed manual transmission (TY856UW1AA) repair and overhaul, clutch system inspection and replacement, gearbox fluid specifications and change intervals.

Drivetrain:

All-Wheel Drive (AWD) system, center differential operation and maintenance, front and rear differential servicing, driveshaft and CV joint inspection and replacement.

Suspension:

Front and rear suspension component diagnosis and replacement (struts, springs, control arms, sway bars, bushings), wheel alignment specifications, STI-specific performance suspension tuning.

Brakes:

Front Brembo 4-piston calipers and rear Brembo 2-piston calipers service, brake fluid type and bleeding procedures, ABS system diagnosis and component testing, parking brake adjustment.

Steering:

Power steering system diagnosis, fluid type and replacement, steering rack inspection and repair, tie rod end replacement.

Electrical System:

Complete wiring diagrams, fuse and relay locations, battery specifications, alternator testing, starter motor service, lighting system troubleshooting, power accessory repair.

Body And Interior:

Door panel removal, seat adjustment and repair, dashboard disassembly, body panel alignment, trim piece replacement, HVAC system components (blower motor, evaporator, condenser).

Cooling System:

Radiator service, cooling fan operation, water pump replacement, thermostat testing, coolant type and capacity.

Fuel System:

Fuel pump and filter replacement, fuel injector servicing, fuel pressure testing, fuel tank removal and inspection.

Exhaust System:

Exhaust manifold, catalytic converter, muffler inspection and replacement, exhaust hanger repair.

Routine Maintenance:

Oil and filter change intervals and procedures, air filter replacement, spark plug replacement, brake fluid flush, differential fluid change, coolant flush.

Troubleshooting:

Diagnostic trouble codes (DTCs) interpretation and troubleshooting flowcharts for common and complex issues, symptom-based diagnostics.

Major Repairs:

Engine rebuilds (short block and long block), transmission overhaul, turbocharger replacement and servicing, clutch assembly replacement, suspension component overhauls.

Component Replacement:

Step-by-step instructions for replacing specific parts such as alternators, starters, water pumps, fuel pumps, brake pads and rotors, spark plugs, ignition coils, and sensors.

Diagnostics:

Detailed procedures for using diagnostic scan tools, interpreting sensor data, performing actuator tests, and diagnosing electrical circuit faults.

Wheel Alignment:

Specific front and rear wheel alignment specifications (camber, caster, toe) for the 2011 WRX STI.

Torque Specifications:

Comprehensive list of all critical torque specifications for engine, transmission, suspension, brakes, and chassis components.

Diagnostic Tools:

Information on necessary diagnostic tools, including OBD-II scanners and Subaru-specific diagnostic equipment.

Service Bulletins:

Likely includes references to or summaries of technical service bulletins (TSBs) relevant to the 2011 model year.

Wiring Diagrams:

Complete, high-resolution wiring diagrams for all vehicle systems, crucial for electrical diagnostics.

Rebuild Procedures:

Detailed, step-by-step rebuild procedures for major mechanical components like the engine and transmission, often including component clearances and assembly techniques.

System Diagrams:

Schematics and diagrams illustrating the operation and interconnections of various vehicle systems.

📊 Manual Specifications

File Type:

PDF

Searchability:

Likely text-searchable for quick information retrieval.

Resolution:

High resolution, suitable for printing specific sections.

Binding:

N/A (Digital)

Paper Quality:

N/A (Digital)

⚙️ Engine Specifications

Engine Type:

2.5L DOHC turbocharged intercooled EJ257 Boxer 4-cylinder

Horsepower:

305 hp @ 6000 rpm

Torque:

290 lb-ft @ 4000 rpm

Fuel Delivery:

Sequential multi-port fuel injection

Recommended Fuel:

Premium Unleaded Gasoline (91 Octane or higher)

Bore X Stroke:

99.5 mm x 79.0 mm

Compression Ratio:

8.4:1

🔧 Transmission

Transmission Type:

6-speed manual

Transmission Model:

TY856UW1AA

Optional Transmission:

None (Manual only for STI)

Dccd:

Driver Controlled Center Differential (DCCD) with automatic and manual modes.

📐 Dimensions

Length:

179.1 inches (4550 mm)

Width:

70.7 inches (1795 mm)

Height:

57.7 inches (1465 mm)

Wheelbase:

103.0 inches (2615 mm)

Curb Weight:

Approx. 3373 lbs (1530 kg)

Gross Weight Rating:

N/A (Vehicle Specific)

Cargo Volume:

11.3 cu ft (Sedan)

🛡️ Safety Features

NHTSA Front Impact:

5-star

NHTSA Side Impact:

5-star

NHTSA Rollover:

4-star

ABS:

4-wheel anti-lock braking system (ABS) with electronic brake-force distribution (EBD).

Traction Control:

Vehicle Dynamics Control (VDC) with sport mode.

Airbags:

Front dual-stage airbags, front side-impact airbags, side-curtain airbags.

Seatbelts:

3-point height-adjustable front seatbelts with pretensioners and load limiters, three 3-point rear seatbelts.

💡 Technology Features

Head Unit:

Base stereo system with CD player, MP3 compatibility, and auxiliary input. Optional navigation system available.

Audio System:

Typically a 6-speaker or 7-speaker system.

Stability Control:

Vehicle Dynamics Control (VDC) with multiple modes.

Auxiliary Input:

Standard 3.5mm auxiliary audio input jack.

🔧 Maintenance

Oil Change:

Every 3,750 miles or 3.75 months for severe driving, 7,500 miles or 7.5 months for normal driving (check manual for exact Subaru recommendations).

Spark Plugs:

Typically around 60,000 miles for iridium-tipped spark plugs.

Timing Belt:

Not applicable (EJ257 uses a timing chain).

Engine Oil:

SAE 5W-30, API SN, ILSAC GF-5 (or equivalent synthetic).

Transmission Fluid:

Subaru Extra-S Gear Oil 75W-90 (GL-5) or equivalent.

Differential Fluid:

Subaru Extra-S Gear Oil 75W-90 (GL-5) or equivalent.

Brake Fluid:

DOT 3 or DOT 4.

Coolant:

Subaru Super Coolant (Blue) or equivalent Subaru-compatible coolant (50/50 mix with distilled water).

Piston Ring Land Failure:

Prevalent issue on EJ257 engines from this era, particularly with aggressive tuning or detonation. Manual should cover inspection procedures.

Head Gasket Leaks:

Less common on EJ257 compared to earlier EJ25, but still a potential concern. Manual should detail inspection and replacement.

Clutch Wear:

High-performance nature can lead to faster clutch wear, especially with aggressive driving. Manual will detail clutch inspection and replacement.

📚 Vehicle History

Rally Origins:

Subaru's long and successful history in World Rally Championship (WRC) directly influences the Impreza WRX STI's design and engineering.

Gc8 To Gr:

The 2011 model represents the GR/GV generation, a significant departure with a hatchback body style (GR) and a sedan option (GV), moving away from the previous GC8 platform.

Manufacturing Location:

Japan

🏆 Awards & Recognition

Performance Acclaim:

Consistently praised by automotive journalists for its handling, acceleration, and AWD system, often winning comparisons in its segment.

Consumer Reports Reliability:

Varies by year and specific components; engine health is crucial. Manual is vital for proper maintenance.

Emissions Certification:

Meets EPA and CARB emissions standards for its model year.