🏷️ Basic Information

Make:

Subaru

Model:

Impreza WRX STI

Year:

2002

Chassis Code:

GDB

Platform:

Subaru Impreza (Third Generation - GD/GG chassis)

👋 Introduction

Segment:

Performance Compact / Rally Homologation Special

Identity:

The 2002 Subaru Impreza WRX STI (known as the 'bug-eye' STI in some markets) represents a significant evolution of Subaru's rally-bred performance sedan, offering a potent blend of everyday usability and track/rally-inspired capability.

Competitors:

Directly competed with other performance sedans of the era such as the Mitsubishi Lancer Evolution, Ford Focus RS, and higher-performance variants of the Honda Civic Si and Volkswagen Golf GTI. Differentiated by its unique turbocharged boxer engine and advanced symmetrical all-wheel-drive system.

Performance Focus:

Developed from Subaru's WRC (World Rally Championship) heritage, emphasizing all-weather traction and dynamic handling.

Engine Type:

Iconic turbocharged EJ207 Boxer engine known for its distinctive sound and power delivery.

Drivetrain:

Symmetrical All-Wheel Drive with Driver Controlled Center Differential (DCCD) for adjustable torque distribution.

Braking System:

Upgraded Brembo braking system for enhanced stopping power.

📋 Manual Details

General Coverage:

Complete factory service and repair information for the 2002 Subaru Impreza WRX STI.

Market Coverage:

Primarily North American market, but with global applicability due to Subaru's international presence.

Estimated Pages:

1500-2000 (estimated based on FSM scope for this model)

Type:

Official Factory Service Manual (FSM) / Repair Manual / Workshop Manual

Language:

English

Format:

PDF

📖 Manual Coverage

Engine:

EJ207 Twin-Scroll Turbocharged Boxer Engine (detailed diagnostics, repair procedures, component specifications, timing belt replacement, turbocharger system, cooling system, lubrication system, fuel injection, ignition system).

Transmission:

TY856 6-Speed Manual Transmission (gearbox removal/installation, clutch system, differential service, lubrication, troubleshooting).

Drivetrain:

All-Wheel Drive System (Active Torque Split - DCCD, front/rear differentials, driveshafts, hubs, bearings).

Brakes:

Brake System (ABS, ventilated front and rear discs, Brembo calipers, hydraulic system, bleeding procedures, component replacement, troubleshooting).

Suspension:

Suspension System (front MacPherson struts, rear multi-link, springs, shock absorbers, control arms, anti-roll bars, alignment specifications).

Steering:

Power Steering System (rack and pinion, hydraulic pump, fluid specifications, troubleshooting).

Electrical:

Electrical System (wiring diagrams, fuse box layout, component testing, lighting, starting and charging system, ECUs, sensors, SRS airbag system, diagnostic codes).

Body:

Body and Exterior (chassis, doors, hood, trunk, bumpers, spoilers, trim, glass, sealing).

Interior:

Interior Trim and Upholstery (dashboard, seats, door panels, headliner, carpet).

HVAC:

Heating, Ventilation, and Air Conditioning (HVAC) system (components, refrigerant, service procedures).

Emissions:

Emissions Control System (catalytic converter, EGR, EVAP, sensor readings, troubleshooting).

Maintenance:

Scheduled maintenance procedures, fluid changes (oil, coolant, brake, transmission, differential), filter replacements, spark plug service, timing belt replacement.

Troubleshooting:

Comprehensive diagnostic procedures for all major systems, including symptom-based troubleshooting guides and diagnostic trouble codes (DTCs).

Repair:

Detailed step-by-step repair instructions for component removal, overhaul, and reinstallation for engine, transmission, drivetrain, brakes, suspension, steering, electrical, and body components.

Specifications:

Torque specifications for all fasteners, engine component clearances, fluid capacities, electrical resistance values, dimensional data.

Diagnostics:

Information on using diagnostic tools, interpreting scan data, and performing actuator tests.

Wiring Diagrams:

Detailed electrical wiring diagrams for all circuits.

Depth:

Comprehensive. Covers everything from basic maintenance and fluid checks to full engine and transmission rebuilds, advanced electrical diagnostics, and chassis alignment.

Diagnostic Tools:

References Subaru-specific diagnostic procedures and likely requires an OBD-II scan tool for advanced diagnostics.

📊 Manual Specifications

Format:

PDF

Searchability:

Likely text-searchable, allowing for quick information retrieval.

Quality:

High-quality digital reproduction of the original factory manual, ensuring clarity of text and diagrams.

Type:

N/A (Digital Download)

Type:

N/A (Digital Download)

Operating Systems:

Compatible with all versions of Windows & Mac.

Software:

Adobe PDF Reader & WinZip (for decompression if applicable).

⚙️ Engine Specifications

Engine Code:

EJ207

Configuration:

Horizontally-opposed (Boxer), 4-cylinder

Displacement:

2.0 Liters (1994 cc)

Aspiration:

Twin-Scroll Turbocharged (IHI VF35 or similar)

Bore X Stroke:

92.0 mm x 75.0 mm

Compression Ratio:

8.0:1

Valve Train:

DOHC, 16 valves (4 valves per cylinder)

Horsepower:

265 PS (approx. 261 hp) @ 6000 RPM (JDM/European spec, US spec was slightly lower for WRX models without the 'STI' designation, but this manual covers the STI variant).

Torque:

343 Nm (approx. 253 lb-ft) @ 4000 RPM (JDM/European spec).

Fuel Delivery:

Sequential Multi-Point Fuel Injection (MPI) with top-feed injectors.

Fuel Type:

Unleaded Gasoline (Premium Unleaded Recommended/Required).

Ignition System:

Electronic Ignition with Coil-on-Plug (COP) or distributor-based depending on exact market variant.

🔧 Transmission

Type:

6-Speed Manual Transmission (TY856)

Type:

N/A (STI models were exclusively manual).

Dccd:

Driver Controlled Center Differential (DCCD) offering manual adjustment of front/rear torque split.

Differentials:

Front Helical Limited-Slip Differential (LSD), Rear Viscous Coupling Limited-Slip Differential (VLSD) or mechanical LSD depending on specific sub-model/market.

Manual Transmission Fluid:

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

Front Differential Fluid:

GL-5 Gear Oil (e.g., 75W-90).

Rear Differential Fluid:

GL-5 Gear Oil (e.g., 75W-90).

📐 Dimensions

Length:

Approx. 4415 mm (173.8 in)

Width:

Approx. 1770 mm (69.7 in)

Height:

Approx. 1410 mm (55.5 in)

Wheelbase:

Approx. 2530 mm (99.6 in)

Track Width Front:

Approx. 1515 mm (59.6 in)

Track Width Rear:

Approx. 1505 mm (59.3 in)

Curb Weight:

Approx. 1420 kg (3131 lbs)

Gross Vehicle Weight Rating:

Varies by market and specific configuration.

Towing Capacity:

Not Specified/Recommended for this performance model.

Wheel Size:

17 x 7.5 inch (standard)

Wheel Bolt Pattern:

5 x 100 mm

Tire Size:

225/45R17 (standard)

🛡️ Safety Features

NHTSA Front Crash:

Good (for similar models tested)

IIHS Side Impact:

Acceptable/Good (for similar models tested)

ABS:

Standard Anti-lock Braking System.

AWD:

Symmetrical All-Wheel Drive with DCCD enhances traction and stability.

Traction Control:

Limited availability or integrated with AWD system depending on market. Some models may feature basic traction control.

Airbags:

Front driver and passenger airbags. Side airbags may be optional depending on market.

Seatbelts:

3-point front and rear seatbelts with pre-tensioners. Driver's seatbelt height adjustment.

Body Structure:

Reinforced chassis and crumple zones designed for occupant protection.

💡 Technology Features

System:

Basic factory radio system, typically with CD player and AM/FM tuner. Limited digital integration typical for the era.

Speakers:

Factory speaker configuration (e.g., 4-speaker or 6-speaker system).

Active:

ABS is the primary active safety technology. DCCD allows for driver control of torque distribution, enhancing dynamic control.

Passive:

Airbags (front, optional side), pre-tensioning seatbelts, and the vehicle's inherently robust chassis contribute to passive safety.

Features:

Minimal by modern standards. May include power windows, power locks, remote keyless entry on some trims. No integrated Bluetooth or navigation typically.

🔧 Maintenance

Oil Change:

Every 3,750 miles (6,000 km) or 6 months for severe driving conditions, 7,500 miles (12,000 km) or 12 months for normal driving (consult FSM for exact schedule).

Timing Belt Replacement:

Every 105,000 miles (168,000 km) or 105 months. Crucial due to interference engine design. Includes replacement of idler pulleys and tensioner.

Coolant Flush:

Every 30,000 miles (48,000 km) or 24 months. Subaru blue coolant is typically recommended.

Spark Plugs:

Platinum or Iridium plugs recommended, interval typically around 60,000-100,000 miles depending on type.

Engine Oil:

5W-30 Synthetic Oil (API SN or higher, ILSAC GF-5 or higher) is generally recommended. Check FSM for specific viscosity and API rating for EJ207.

Engine Oil Capacity:

Approx. 4.5 Liters (4.8 US Quarts) with filter change.

Coolant Type:

Subaru Super Coolant (Blue) or equivalent long-life silicate-free coolant.

Brake Fluid:

DOT 3 or DOT 4 brake fluid.

Piston Ring Land Cracking:

A known issue with some EJ207 engines, particularly when subjected to aggressive tuning or prolonged high heat. The manual will provide specifications for inspecting and potentially addressing this. Part numbers for upgraded pistons may be discussed in specialist sections.

Head Gasket Leaks:

While less common on the EJ207 compared to some earlier EJ engines, head gasket integrity is crucial. The manual will outline procedures for inspection and replacement, including correct torque sequences and gasket types.

Clutch Wear:

Performance clutches can experience increased wear with spirited driving. Manual covers clutch inspection, replacement, and torque specifications for clutch assembly bolts.

Dccd Malfunction:

The Driver Controlled Center Differential unit can sometimes develop issues. The manual will aid in diagnosing electrical faults related to the DCCD system.

📚 Vehicle History

Heritage:

Subaru's reputation for building robust, all-wheel-drive vehicles is deeply rooted in its success in motorsports, particularly the World Rally Championship.

Generation:

This 2002 model marks the introduction of the second generation Impreza chassis (GD/GG), also known as the 'Bugeye' for its distinctive headlights. It represented a significant styling and engineering update over the outgoing GC/GF chassis.

Sti Development:

The STI (Subaru Tecnica International) variant is a homologation special for WRC, featuring a more powerful engine, upgraded suspension, brakes, and drivetrain components compared to the standard WRX.

Production Start:

2000 (for the second generation Impreza platform)

Production End For Chassis:

2007 (for the GD/GG chassis)

Manufacturing Location:

Japan (Various Subaru plants, typically Gunma Prefecture)

🏆 Awards & Recognition

Motorsport:

The Impreza platform, especially the STI variants, has a storied history of success in the World Rally Championship, earning numerous driver and manufacturer titles. This motorsport pedigree is a key aspect of the model's appeal.

Car And Driver:

The Impreza WRX (and by extension the STI) was frequently recognized by automotive publications like Car and Driver, often appearing on '10Best' lists for its performance value and handling capabilities.

Enthusiast Acclaim:

Highly regarded by automotive enthusiasts for its engaging driving experience, potent powertrain, and rally-inspired performance.