Segment:
Performance Compact Sedan/Hatchback (WRC Homologation Special)
Target Audience:
Enthusiasts, performance drivers, rally sport fans
Key Competitors:
Mitsubishi Lancer Evolution, Volkswagen Golf GTI, Ford Focus RS, Honda Civic Type R
Performance Focus:
Symmetrical All-Wheel Drive, turbocharged Boxer engine, performance-tuned suspension, aggressive styling
Manual Value Proposition:
Provides in-depth, professional-level repair and maintenance guidance for the specialized WRX STI variant
Major Topics:
Engine, Transmission, Drivetrain, Suspension, Brakes, Electrical Systems, HVAC, Bodywork, Diagnostics, Maintenance, Repair, Troubleshooting
Type:
Service and Repair Workshop Manual
Engine Mechanical:
Engine assembly, cylinder heads, pistons, crankshaft, timing belt/chain, lubrication system, cooling system
Engine Performance:
Fuel injection system, ignition system, turbocharger, intercooler, emission control systems (EVAP, secondary air injection)
Transmission Drivetrain:
Manual transmission (TY856), clutch system, all-wheel drive system (DCCD), differentials (front, rear, center), driveshafts, axles
Suspension Steering:
Front and rear suspension components (struts, springs, control arms, sway bars), power steering system, steering rack
Brakes:
Brake system components (calipers, rotors, pads, master cylinder, ABS), parking brake
Electrical Systems:
Wiring diagrams, battery, charging system, starting system, lighting (headlights, taillights, interior), power windows, mirrors, central locking
HVAC:
Air conditioning system, heating system, ventilation, blower motor, climate control unit
Bodywork Interior:
Exterior panels, doors, hood, trunk, bumpers, interior trim, seats, airbags
Diagnostics:
OBD-II diagnostic codes, troubleshooting procedures, sensor testing, ECU diagnosis
Scheduled Maintenance:
Oil changes, filter replacements, fluid flushes, spark plug replacement, inspections
Engine Repair:
Engine rebuilds, head gasket replacement, turbocharger overhaul, timing belt/chain replacement procedures
Transmission Service:
Transmission fluid change, clutch replacement, drivetrain component inspection and repair
Brake Service:
Brake pad and rotor replacement, brake fluid flush, caliper overhaul
Electrical Troubleshooting:
Fault finding for various electrical systems using wiring diagrams and diagnostic steps
Body Repair:
Panel replacement, dent repair, bumper repair, door mechanism adjustment
Depth:
Comprehensive from basic maintenance to complex overhauls and diagnostics, suitable for professional mechanics and experienced DIYers
NHTSA Overall Rating:
5-Star (2015 Model Year Impreza)
ABS:
4-wheel Anti-lock Braking System (ABS)
Traction Control:
Vehicle Dynamics Control (VDC) with Sport Mode
AWD:
Subaru Symmetrical All-Wheel Drive
Airbags:
Front dual-stage airbags, front side-impact airbags, side-curtain airbags, driver's knee airbag
Seatbelts:
3-point front and rear seatbelts with pretensioners and force limiters
Head Unit:
Standard touchscreen infotainment system with CD player, AM/FM/HD Radio, USB/iPod control, Bluetooth connectivity
Vehicle Dynamics Control:
Advanced VDC system with Sport Mode for enhanced handling and stability control
All Wheel Drive Control:
DCCD allows driver to adjust center differential lockup for various driving conditions.
Bluetooth:
Bluetooth hands-free phone and audio streaming
Oil Change Interval:
Every 3,750 miles or 6 months (severe duty) / 7,500 miles or 12 months (normal duty)
Engine Oil Type:
SAE 5W-30, API SN/SP, ILSAC GF-5/GF-6A certified synthetic oil recommended
Oil Filter Part Number:
Subaru: 15208AA100, Aftermarket: Wix 57712, K&N HP-3001
Coolant Type:
Subaru Super Coolant (Blue) or equivalent silicate-free, long-life coolant
Transmission Fluid Type:
Subaru Extra MT (75W-90 GL-5) for 6MT
Differential Fluid Type:
Subaru Extra-S (75W-90 GL-5) for Front and Rear Diffs, and DCCD Center Diff
Brake Fluid Type:
DOT 3 or DOT 4 brake fluid
Engine Ringland Failure:
Potential for ringland failure on piston #4 due to detonation, especially with aggressive tuning or poor fuel. Manual details proper diagnosis and repair.
Clutch Wear:
High-performance clutch can wear faster under aggressive driving. Manual provides clutch inspection and replacement procedures.
Turbo Failure:
Turbocharger bearing failure can occur due to lack of lubrication or oil contamination. Manual covers turbo inspection and replacement.
Rally Roots:
Subaru's long and successful history in World Rally Championship (WRC) series, influencing the WRX STI's development.
Generation:
Third Generation (GR/GV Chassis, 2008-2014, with facelift in 2011) and Fourth Generation (VA Chassis, starting 2015). This manual covers the transition and initial VA chassis.
Production Years:
2007-2014 (GR/GV), 2015-2021 (VA)
Manufacturing Location:
Ota City, Gunma Prefecture, Japan