Vehicle Segment:
Compact Car / Sport Compact
Brand Philosophy:
Subaru's reputation for symmetrical all-wheel drive, boxer engines, and rally heritage.
Key Competitors:
Honda Civic, Toyota Corolla, Mitsubishi Lancer, Mazda Protege, Nissan Sentra.
Drivetrain Advantage:
Standard Symmetrical All-Wheel Drive (AWD) on most models, providing superior traction and stability.
Engine Layout:
Horizontally-opposed (Boxer) engine, offering a lower center of gravity and smoother operation.
Performance Variants:
Availability of performance-oriented WRX and STI models (though this manual primarily covers base Impreza variants).
Engine Mechanics:
Engine overhaul, cylinder head, block, pistons, crankshaft, camshafts, valve train, timing belt/chain, cooling system, lubrication system, fuel system (injection), ignition system, emission controls.
Transmission Drivetrain:
Manual transmission (all gears, clutch, linkages), automatic transmission (operation, fluid service, solenoids), transfer case, differential, driveshafts, CV joints, AWD system.
Suspension Steering:
Front suspension (struts, control arms, ball joints, bushings), rear suspension (multi-link, trailing arms, bushings), steering gear, power steering system, wheel alignment specifications.
Brakes:
Front and rear brake systems (disc/drum), ABS system (components, diagnostics, bleeding), brake fluid, parking brake, hydraulic lines.
Electrical Electronics:
Wiring diagrams, fuse boxes, relays, battery, charging system (alternator), starting system (starter), lighting systems (headlights, taillights, interior), instrument panel, gauges, power accessories (windows, locks, mirrors), audio system, ECU/ECM diagnostics.
Body Chassis:
Body panel removal and installation, doors, hood, trunk, bumpers, interior trim, glass, rust prevention, corrosion control, chassis lubrication.
HVAC:
Heating, Ventilation, and Air Conditioning (HVAC) system components, refrigerant service, blower motor, climate control panel.
Scheduled Maintenance:
Oil changes, filter replacements (oil, air, fuel, cabin), fluid checks and top-offs, tire rotation, brake inspection, spark plug replacement, timing belt replacement intervals.
Troubleshooting Diagnostics:
Diagnostic trouble codes (DTCs), symptom-based troubleshooting, circuit testing, component testing, common problem solutions.
Repair Overhaul:
Step-by-step instructions for engine rebuilds, transmission overhauls, brake caliper replacement, suspension component replacement, electrical component repair.
Installation Replacement:
Procedures for installing new parts, replacing worn components, fitting aftermarket accessories.
Diagnostic Tools:
Use of OBD-II scanners, multimeters, pressure gauges, specialized Subaru diagnostic equipment.
Torque Specifications:
Precise torque values for all critical fasteners, including engine, transmission, suspension, and wheel lug nuts.
Electrical Schematics:
Detailed wiring diagrams for all vehicle systems, including component locations and wire colors.
Dimensional Data:
Specifications for alignments, component measurements, and tolerances.
Engine Code:
EJ22 (2.2L), EJ25 (2.5L SOHC and DOHC)
Displacement Liters:
2.2 L (2210 cc) and 2.5 L (2457 cc)
Cylinders:
4 (Horizontally Opposed Boxer)
Bore X Stroke:
2.2L: 96.9 mm x 75.0 mm; 2.5L SOHC: 99.5 mm x 79.0 mm; 2.5L DOHC (WRX): 99.5 mm x 79.0 mm (approximate)
Horsepower Hp:
2.2L: ~135 hp @ 5600 rpm; 2.5L SOHC: ~165 hp @ 5600 rpm; 2.5L DOHC Turbo (WRX): ~227 hp @ 6000 rpm (for 2001 WRX)
Torque Lb Ft:
2.2L: ~140 lb-ft @ 4400 rpm; 2.5L SOHC: ~170 lb-ft @ 4000 rpm; 2.5L DOHC Turbo (WRX): ~217 lb-ft @ 4000 rpm (for 2001 WRX)
Fuel Delivery:
Electronic Fuel Injection (EFI) with multi-port injection.
Fuel Type:
Unleaded Gasoline (87 octane recommended for naturally aspirated; premium for WRX/STI).
Fuel Pump Type:
In-tank electric fuel pump.
Length:
Approx. 169.2 inches (4300 mm)
Width:
Approx. 67.1 inches (1704 mm)
Height:
Approx. 55.7 inches (1415 mm)
Wheelbase:
Approx. 99.8 inches (2535 mm)
Track Width Front:
Approx. 58.1 inches (1475 mm)
Track Width Rear:
Approx. 57.3 inches (1455 mm)
Ground Clearance:
Approx. 6.1 inches (155 mm)
Curb Weight Kg:
Approx. 1250-1350 kg (depending on trim and drivetrain)
Gross Vehicle Weight Rating Kg:
Approx. 1700-1800 kg (depending on configuration)
Towing Capacity Kg:
Not typically specified or recommended by Subaru for this model.
NHTSA Front Impact:
Driver: 4 stars, Passenger: 4 stars (for comparable models/years, specific data may vary).
NHTSA Side Impact:
Front: 4 stars, Rear: 4 stars (for comparable models/years, specific data may vary).
ABS:
Anti-lock Braking System standard on many trims, optional on others.
Traction Control:
Rarely available on standard Impreza models of this era; more common on WRX.
Airbags:
Driver and front passenger airbags standard.
Seatbelts:
Three-point seatbelts with pretensioners and load limiters for front seats.
Child Seat Anchors:
LATCH system not standard; typically utilizes seatbelt anchoring for child seats.
Oil Change Interval Miles:
Every 3,750 miles or 6 months, whichever comes first.
Air Filter Replacement Miles:
Every 15,000 miles or 12 months.
Fuel Filter Replacement Miles:
Every 30,000 miles (in-tank filter, though often replaced less frequently).
Spark Plug Replacement Miles:
Every 30,000 miles (NGK Platinum or Iridium recommended).
Timing Belt Replacement Miles:
Critical: Every 60,000-90,000 miles or 5-7 years (due to interference engine design). Includes tensioner and idler pulleys.
Engine Oil Type:
API SG or SH, SAE 5W-30 or 10W-30 (check owner's manual for specific climate recommendations).
Engine Oil Capacity Liters:
Approx. 4.2 Liters (4.4 US Quarts) with filter change.
Coolant Type:
Ethylene Glycol based coolant (Subaru Super Coolant or equivalent), pre-mixed 50/50 with distilled water.
Coolant Capacity Liters:
Approx. 6.0 Liters (6.3 US Quarts).
Brake Fluid Type:
DOT 3 or DOT 4.
Head Gaskets:
Common failure point, especially on EJ25 SOHC engines (externally leaking coolant). Manual will detail inspection and replacement.
Oil Leaks:
Valve cover gaskets, oil pan gaskets, and crankshaft seals can leak over time.
Transmission Synchronizers:
Wear in manual transmission synchronizers, particularly 2nd gear, can lead to shifting difficulties.
Power Steering Pump:
Noise or stiffness can indicate an aging power steering pump or leaks in the system.
Radiator Corrosion:
Plastic end tanks on radiators can become brittle and crack, leading to leaks.