🏷️ Basic Information

Make:

Subaru

Model:

Impreza

Year:

2002

Trim Level Covered:

WRX STI

Body Styles Covered:

Sedan and Wagon

Chassis Code:

GD/GG

Engine Codes Covered:

EJ20G (DOHC Turbocharged), EJ201/EJ202 (SOHC Naturally Aspirated)

👋 Introduction

Market Position:

The 2002 Subaru Impreza WRX STI (GD/GG chassis) represents the pinnacle of Subaru's performance offerings for that era, built upon the success of its rally heritage. This model is highly sought after by enthusiasts for its turbocharged boxer engine, symmetrical all-wheel-drive system, and sporty handling characteristics.

Competitive Analysis:

Competed against performance variants of cars like the Mitsubishi Lancer Evolution, Ford Focus RS, and Volkswagen Golf GTI. Its unique boxer engine and AWD system provided distinct advantages in traction and handling, particularly in adverse conditions.

Key Features:

Turbocharged Boxer Engine, Symmetrical All-Wheel Drive, performance-tuned suspension, sport seats, aerodynamic body kit, advanced intercooler system, robust drivetrain.

Performance Enhancements Sti:

The WRX STI variant featured a more powerful engine, upgraded suspension components (often inverted front struts), larger brakes, a more aggressive aerodynamic package, and the signature DCCD system for advanced torque distribution.

📋 Manual Details

Coverage Areas:

General Maintenance, SOHC Engine, DOHC Engine, Transmission, Chassis, Body, Wiring

Page Count:

Estimated 1000+ pages (typical for a comprehensive factory service manual)

Manual Type:

Factory Service Workshop Repair Manual

Manual Purpose:

A comprehensive guide for diagnosing, repairing, and maintaining the 2002 Subaru Impreza, covering all aspects of the vehicle for professional and DIY use.

Language:

English

Format:

PDF Download

📖 Manual Coverage

Systems Covered:

Engine mechanical (SOHC & DOHC), fuel system, ignition system, exhaust system, cooling system, lubrication system, starting system, charging system, manual transmission, automatic transmission (if applicable), drivetrain (AWD), suspension system (front & rear), steering system, braking system (including ABS), HVAC system, body electrical, interior/exterior trim, chassis components, collision repair, diagnostic procedures, wiring diagrams.

Interior Body Systems:

Interior trim removal and installation, door mechanisms, window regulators, seat removal, dashboard disassembly, headliner, carpeting, exterior body panel replacement, bumpers, fenders, doors, hood, trunk lid, glass replacement.

Electrical System:

Comprehensive wiring diagrams for all major systems including engine control, lighting, audio, HVAC, power accessories, security system, ABS, SRS (Airbag) system. Includes troubleshooting guides and component locations.

Procedures Included:

Routine maintenance (oil changes, filter replacements, inspections), engine diagnostics and repair (timing belt replacement, head gasket repair, turbocharger service), transmission service and overhaul, brake system bleeding and component replacement, suspension and steering alignment and component replacement, electrical system troubleshooting and repair, body panel repair and replacement, air conditioning system servicing, diagnostic trouble code (DTC) interpretation and resolution, wiring harness repair, safety system checks.

Engine Rebuild Procedures:

Detailed procedures for engine disassembly, inspection, component replacement (pistons, rings, bearings, valves, camshafts), torque specifications for all fasteners, engine assembly, and break-in procedures.

Transmission Repair:

Complete overhaul procedures for both manual and automatic transmissions, including gear inspection, synchro replacement, clutch assembly service, torque converter replacement, and transmission fluid change procedures.

Wheel Alignment:

Detailed specifications and procedures for front and rear wheel alignment (camber, caster, toe), including necessary adjustments.

Technical Depth:

Comprehensive, covering everything from basic adjustments and maintenance to complete engine and transmission overhauls, advanced diagnostic procedures, and detailed wiring schematics. Suitable for professional technicians and advanced DIY enthusiasts.

Diagnostic Charts:

Includes detailed diagnostic flowcharts for common symptoms, fault codes, and electrical system issues, aiding in systematic troubleshooting.

Emission Controls:

Information on emission control systems, components, diagnostic procedures, and troubleshooting related to emissions compliance.

📊 Manual Specifications

File Format:

PDF (Portable Document Format), typically with searchable text for easy navigation.

Searchability:

High-quality PDF with selectable text for keyword searching, allowing users to quickly find specific repair or diagnostic information.

Print Quality:

High-resolution scans or native digital files, ensuring clarity of diagrams, schematics, and text.

Binding Type:

N/A (Digital Download)

Paper Type:

N/A (Digital Download)

⚙️ Engine Specifications

Primary Engine:

2.0L EJ207 DOHC Turbocharged Boxer Engine (WRX STI)

Ej201 Ej202 Specs:

2.0L EJ201/EJ202 SOHC Naturally Aspirated Boxer Engine. Approx. 125-145 hp depending on specific market/tune.

Horsepower Sti:

Approx. 265 PS (195 kW; 261 hp) at 6,000 rpm (JDM/European specs)

Torque Sti:

Approx. 343 Nm (253 lb-ft) at 4,000 rpm (JDM/European specs)

Engine Layout:

Horizontally-opposed (Boxer)

Fuel System:

Multi-point Fuel Injection (MPI), Turbocharged with intercooler

Fuel Type Required:

Premium Unleaded Gasoline (91 octane or higher recommended for turbo models).

Engine Codes Covered:

EJ207 (DOHC Turbocharged - WRX STI), EJ201/EJ202 (SOHC Naturally Aspirated - standard Impreza models)

🔧 Transmission

Standard Transmission Sti:

6-speed Manual Transmission

Optional Transmission:

4-speed Automatic Transmission (typically for non-STI models)

Drivetrain Type:

Symmetrical All-Wheel Drive (AWD)

Differential Type:

Driver Controlled Center Differential (DCCD) on WRX STI models

📐 Dimensions

Wheelbase:

Approx. 2510 mm (98.8 in)

Length:

Approx. 4405 mm (173.4 in)

Width:

Approx. 1750 mm (68.9 in)

Height:

Approx. 1410 mm (55.5 in)

Curb Weight Sti:

Approx. 1430 kg (3153 lbs)

Gross Vehicle Weight Rating:

Varies by model/trim, typically around 1900-2000 kg (4189-4409 lbs) for STI.

Seating Capacity:

5 occupants

Cargo Volume:

Sedan: Approx. 11.6 cu ft. Wagon: Approx. 30.4 cu ft (rear seats up).

🛡️ Safety Features

NHTSA Front Impact:

4 stars (driver), 4 stars (passenger) for 2002 model year.

Active Features:

Anti-lock Braking System (ABS), Electronic Brake-force Distribution (EBD), All-Wheel Drive system.

Passive Features:

Front airbags, side airbags (optional/availability varies by market), front seatbelt pretensioners, crumple zones.

💡 Technology Features

Infotainment System:

Basic factory radio with CD player, possibly cassette. Limited advanced infotainment features by modern standards.

Driver Assistance Features:

ABS, EBD. Limited to no other advanced driver-assistance systems (ADAS) on this model year.

Connectivity Options:

Basic audio connectivity. No Bluetooth or USB integration from the factory.

🔧 Maintenance

Oil Change Interval:

Every 3,750 miles (6,000 km) or 3.75 months, whichever comes first (severe driving conditions). Consult manual for normal conditions.

Timing Belt Replacement:

Every 60,000 miles (96,000 km) or 4 years, whichever comes first, for EJ20 engines.

Engine Oil Type Sti:

SAE 5W-30 or 5W-40, API SG, SH, SJ or ILSAC GF-2, GF-3. Check manual for specific viscosity based on climate.

Coolant Type:

Subaru Super Coolant (Blue) or equivalent ethylene glycol-based coolant with Subaru's additive package. 50/50 mix with distilled water.

Transmission Fluid Type Manual Sti:

Subaru Extra-S Gear Oil API GL-5, SAE 75W-90 (or equivalent high-quality synthetic).

Differential Fluid Type Front Rear:

API GL-5, SAE 75W-90 (front and rear differentials).

Brake Fluid Type:

DOT 3 or DOT 4 brake fluid.

Power Steering Fluid Type:

Subaru Genuine Power Steering Fluid or equivalent ATF (Dexron III type, check manual for specifics).

Common Issues:

Head gasket failures (especially on non-turbo models), ringland failure on heavily modified turbo engines, clutch wear, turbocharger issues (oil starvation), rear differential pinion seal leaks, rust (especially in fender wells and rocker panels).

Turbo Specific Issues:

Oil feed line issues on turbo models, leading to turbo failure if not addressed. Regular oil changes are critical to prevent sludge buildup.

📚 Vehicle History

Brand Heritage:

Subaru, a division of Subaru Corporation (formerly Fuji Heavy Industries), has a long history of producing reliable and capable vehicles, with a particular emphasis on all-wheel-drive technology and boxer engines, deeply influenced by their success in the World Rally Championship (WRC).

Model Evolution:

The second generation Impreza (GD/GG) debuted in 2000 and brought a significant redesign, including the iconic 'bug eye' headlights for early models. The WRX STI variant was introduced as a homologation special for rally racing, offering enhanced performance over the standard WRX.

Chassis Codes:

GD (Sedan) and GG (Wagon) chassis designations for this generation.

Production Location:

Japan (Gunma Plant)

Production Years For Gd Gg:

2000-2007

🏆 Awards & Recognition

Rally Heritage:

The Impreza WRX STI platform is synonymous with Subaru's extensive success in the World Rally Championship, winning multiple driver and manufacturer championships, which significantly boosted the model's global prestige and performance credentials.