🏷️ Basic Information

Make:

Subaru

Model:

Impreza

Year:

2002

Chassis Code:

GDA/GDB (WRX/STi), GG/GD (non-WRX)

👋 Introduction

Market Position:

The 2002 Subaru Impreza (second generation, 'GD' chassis) solidified Subaru's reputation for offering sporty, all-wheel-drive vehicles accessible to enthusiasts. It competed against the Mitsubishi Lancer Evolution (though not directly in all markets), Ford Focus SVT, and Volkswagen GTI.

Competitive Analysis:

The Impreza offered a unique combination of standard Symmetrical All-Wheel Drive and horizontally opposed boxer engines, providing excellent traction and a low center of gravity. The WRX variants brought rally-inspired performance to a broader audience, distinguishing it from front-wheel-drive competitors.

Key Features:

Standard Symmetrical All-Wheel Drive, turbocharged EJ205 engine (WRX), available naturally aspirated EJ25 engines, rally heritage, practical hatchback and sedan body styles, robust chassis.

📋 Manual Details

Systems Covered Overview:

Engine, drivetrain, chassis, body, electrical, HVAC, emissions, diagnostics, maintenance.

Page Count:

Approximately 2000+ pages (typical for a complete factory service manual, actual may vary).

Manual Type:

Factory Service Manual (FSM) / Repair Manual

Language:

English

Format:

Digital (PDF)

📖 Manual Coverage

Engine:

EJ205 (2.0L Turbo), EJ251/EJ253 (2.5L NA), EJ207 (2.0L JDM/EDM Turbo - WRX STI).

Powertrain:

Manual and automatic transmissions (e.g., TY754/TY856 for manual, TZ1B for auto), All-Wheel Drive system (Symmetrical AWD) operation and diagnosis, differentials, driveshafts, axles.

Chassis:

Suspension (front MacPherson strut, rear multi-link), steering (rack and pinion), brakes (front vented discs, rear discs), wheel bearings, subframes, exhaust system.

Electrical:

Wiring diagrams, lighting, power distribution, starter, alternator, battery, ignition system, sensors (crank, cam, knock, O2, MAP), ECU pinouts, fuses, relays, diagnostics for electrical faults.

Body:

Body panels, doors, windows, locks, glass, interior trim, exterior trim, bumpers, chassis stiffness information.

HVAC:

Air conditioning system operation, refrigerant charging, heater core, blower motor, controls, climate control system.

Emissions:

Emission control systems, catalytic converter, EGR system, evaporative emission control (EVAP), diagnosis of emission-related faults, OBD-II system.

Routine Maintenance:

Oil changes, filter replacements (oil, air, cabin), spark plug replacement, fluid level checks and top-offs, tire rotation and pressure checks.

Engine Repair:

Engine removal and installation, cylinder head gasket replacement, piston and ring replacement, valve adjustment, timing belt replacement (for EJ25 naturally aspirated models), turbocharger inspection and replacement (for WRX models).

Transmission Service:

Transmission fluid change and fill, clutch inspection and replacement, torque converter inspection (automatic), transmission removal and installation, clutch hydraulic system service.

Brake System:

Brake pad and rotor replacement, brake caliper service, brake fluid flush and bleed, parking brake adjustment, ABS system diagnosis.

Electrical Diagnostics:

Troubleshooting electrical circuits using wiring diagrams, testing sensors, actuators, ECUs, instrument cluster repair, power window/lock troubleshooting.

Suspension Steering:

Strut and shock absorber replacement, ball joint and tie rod end replacement, power steering pump and rack inspection/replacement, wheel alignment specifications.

Bodywork Interior:

Door panel removal, headliner replacement, bumper cover installation, headlight/taillight replacement, door lock actuator replacement.

Diagnostic Procedures:

Detailed diagnostic flowcharts for common and uncommon issues, use of Subaru Select Monitor (SSM) or equivalent diagnostic tools, trouble code (DTC) explanations and troubleshooting.

Rebuild Procedures:

Complete engine rebuild specifications (bore, hone, torque sequences), transmission overhaul procedures, differential rebuild instructions.

Component Specifications:

Tightening torques for all critical fasteners, clearance measurements, resistance values for electrical components, pressure specifications for fuel and oil systems.

📊 Manual Specifications

File Format:

PDF

Print Quality:

High-resolution scans suitable for clear printing of text and diagrams.

Binding Type:

N/A (Digital - PDF)

Paper Type:

N/A (Digital - PDF)

⚙️ Engine Specifications

Engine Options:

2.5L EJ251/EJ253 SOHC Naturally Aspirated (NA), 2.0L EJ205 DOHC Turbocharged (WRX), 2.0L EJ207 DOHC Turbocharged (WRX STI - JDM/EDM).

Ej251 Specs:

Displacement: 2457cc, Power: ~165 hp @ 5600 rpm, Torque: ~166 lb-ft @ 4000 rpm.

Ej205 Specs:

Displacement: 1994cc, Power: ~227 hp @ 5600 rpm, Torque: ~217 lb-ft @ 4000 rpm (US WRX).

Ej207 Specs:

Displacement: 1994cc, Power: ~260-280 hp @ 6000 rpm, Torque: ~250-260 lb-ft @ 4000 rpm (JDM/EDM WRX STI).

Fuel System Type:

Multi-point fuel injection (MPI), sequential fuel injection.

Recommended Fuel:

87 Octane (NA), 91 Octane Recommended (WRX/STI).

ECU Type:

Subaru ECUs, often Hitachi or Denso ECUs.

🔧 Transmission

Standard Transmission:

5-speed manual transmission (e.g., TY754 for NA, TY856 for WRX).

Optional Transmission:

4-speed automatic transmission (e.g., TZ1B).

AWD System:

Symmetrical All-Wheel Drive with viscous coupling center differential. Front LSD, rear LSD for STI models.

Manual Transmission Fluid:

Subaru Extra-S (or equivalent) 75W-90 API GL-5 gear oil.

Automatic Transmission Fluid:

Subaru ATF-HP or Dexron III/Mercon compatible fluid.

📐 Dimensions

Wheelbase:

103.1 inches (2619 mm)

Length:

Sedan: 177.4 inches (4506 mm), Wagon: 177.8 inches (4516 mm)

Width:

68.1 inches (1730 mm)

Height:

Sedan: 55.5 inches (1410 mm), Wagon: 56.1 inches (1425 mm)

Curb Weight:

Approx. 2900 - 3200 lbs (1315 - 1451 kg) depending on trim and drivetrain.

Cargo Volume:

Wagon models offer significantly more cargo volume than sedans.

Wheel Bolt Pattern:

5x100mm

Tire Sizes:

NA Models: 205/55R16, WRX Models: 205/50R16 (early), 205/55R16 (later). STI: 215/40R17 or 225/45R17.

🛡️ Safety Features

NHTSA Ratings 2002:

Frontal: 4 Stars (Driver and Passenger). Side: Not Rated or 3 Stars (depends on side airbags).

Active Safety Features:

Standard Symmetrical All-Wheel Drive, Anti-lock Braking System (ABS), available Subaru Vehicle Dynamics Control (VDC) on some higher trims.

Passive Safety Features:

Front airbags, available front side-impact airbags, three-point seatbelts with pre-tensioners, crumple zones.

💡 Technology Features

Infotainment System:

Basic AM/FM/CD stereo systems were standard. Higher trims might have premium audio or cassette players. Navigation was not commonly available.

Driver Assistance Features:

Limited to ABS and optional VDC. No advanced electronic driver aids like adaptive cruise control, lane keeping assist, or automatic emergency braking.

Connectivity Options:

No Bluetooth, USB, or smartphone integration. Aux input might be present on some aftermarket head units.

🔧 Maintenance

Oil Change Interval:

Every 3,750 miles (6,000 km) or 3 months for severe driving, 7,500 miles (12,000 km) or 6 months for normal driving (check manual for exact details and oil type).

Timing Belt Replacement:

For EJ25 SOHC engines: 105,000 miles (168,000 km) or 105 months. EJ20 engines are timing chain driven.

Spark Plug Replacement:

NA EJ25: ~60,000 miles. WRX EJ205: typically 30,000 miles (or check specific plug type).

Coolant Type:

Subaru Super Coolant (Blue) or compatible silicate-free, OAT (Organic Acid Technology) coolant. 50/50 mix with distilled water.

Engine Oil Capacity:

4.8 US quarts (4.5 liters) with filter for EJ25, 4.2 US quarts (4.0 liters) with filter for EJ205.

Brake Fluid Type:

DOT 3 or DOT 4 brake fluid.

Head Gasket Failure:

Common on naturally aspirated EJ25 engines of this era. Symptoms include coolant loss, white smoke, overheating. Often requires replacement of head gaskets, head bolts, and potentially resurfacing heads.

Wrx Turbo Issues:

Turbocharger seal failure (leading to oil consumption/smoke), blown intercooler hoses, clutch wear due to aggressive driving.

Suspension Wear:

Front struts and rear trailing arm bushings can wear out over time, leading to clunking noises and poor handling.

Evap System Leaks:

Check Engine Light (CEL) due to EVAP purge valve or canister issues are relatively common.

Oil Filter Part Number:

Subaru OEM: 15208AA100 or equivalent (e.g., Wix 57045).

Air Filter Part Number:

Subaru OEM: 16546AA060 or equivalent.

📚 Vehicle History

Brand Heritage:

Subaru, a division of Fuji Heavy Industries, has a long history in aviation engineering, which influences its automotive designs, particularly the boxer engine and AWD systems.

Second Generation Impreza:

The 2002 model marks the beginning of the second generation ('GD' chassis) for the Impreza, introduced globally. It featured a distinctive 'bug-eye' headlight design that was later revised in 2004 ('hawk-eye') and 2006 ('ass-eye').

Production Locations:

Mainly produced in Gunma, Japan.

Production Years For Gd Chassis:

2002-2007

🏆 Awards & Recognition

Car And Driver Five Best:

The Subaru Impreza WRX was named to Car and Driver's 10Best list multiple times, including in 2002.

Rally Championships:

The Impreza platform has a strong lineage in motorsports, achieving multiple World Rally Championship (WRC) titles.