Engine Mechanical:
Complete engine disassembly, assembly, inspection, and repair for all engine variants including EJ20, EJ25 (Naturally Aspirated and Turbocharged) including timing belt, cylinder heads, pistons, crankshaft, lubrication system, cooling system.
Engine Management:
Fuel injection system (EFI), ignition system, emissions control systems (EVAP, secondary air injection), ECU diagnostics, sensor and actuator testing, OBD-II troubleshooting.
Transmission Manual:
Service and repair procedures for 5-speed and 6-speed manual transmissions (e.g., TY754, TY856), clutch system diagnosis and replacement, driveline components (driveshafts, differentials).
Transmission Automatic:
Service and repair procedures for 4-speed automatic transmissions (e.g., 4EAT), torque converter operation, transmission control module (TCM), fluid service, valve body diagnosis.
Suspension Steering:
Front and rear suspension component replacement and alignment (struts, control arms, bushings, sway bars), power steering system diagnosis and repair, steering rack and pump.
Brakes:
Brake system overhaul, ABS diagnostics and component testing, brake fluid flush, rotor and pad replacement, caliper service.
Electrical Lighting:
Wiring diagrams, lighting system troubleshooting (headlights, taillights, interior lights), fuse and relay identification, bulb replacement procedures.
HVAC:
Air conditioning system servicing, heater core replacement, climate control system diagnosis, blower motor and fan control.
Body Interior:
Body panel removal and installation, interior trim components, door hardware, glass replacement, seat mechanisms.
Maintenance:
Scheduled maintenance intervals, oil and filter changes, spark plug replacement, coolant service, differential fluid change, air filter replacement.
Troubleshooting:
Diagnostic flowcharts for common problems, symptom-based troubleshooting guides, error code interpretation.
Repair Rebuild:
Detailed step-by-step instructions for component removal, disassembly, repair, reassembly, and installation.
Diagnostics:
ECM/PCM data stream interpretation, sensor data analysis, actuator testing procedures using diagnostic tools.
Depth:
Comprehensive. Covers everything from basic scheduled maintenance to complete engine and transmission overhauls, including advanced electrical diagnostics and body repair.
Primary Engine Naturally Aspirated
Displacement:
2.5 Liters (2457 cc)
Configuration:
Horizontally-Opposed (Boxer), 4-Cylinder, DOHC, 16-Valve
Horsepower:
165 hp @ 5600 rpm (approx.)
Torque:
166 lb-ft @ 3600 rpm (approx.)
Primary Engine Turbocharged Wrx
Displacement:
2.0 Liters (1994 cc)
Configuration:
Horizontally-Opposed (Boxer), 4-Cylinder, DOHC, 16-Valve, Turbocharged with Intercooler
Horsepower:
227 hp @ 5600 rpm (approx.)
Torque:
217 lb-ft @ 4000 rpm (approx.)
Engine Type:
Naturally Aspirated (2.5L) and Turbocharged (2.0L WRX, 2.5L STI)
System Type:
Multi-point Fuel Injection (MPI)
Fuel Type:
Unleaded Gasoline (91 Octane or higher recommended for Turbo models)
Oil Change:
Every 3,750 - 7,500 miles or 6 months, depending on driving conditions and oil type used (consult manual for specifics).
Timing Belt:
Replace every 90,000 - 105,000 miles or 7 years for naturally aspirated and 2.0L turbo models. STI models may have different intervals. Crucial to follow closely to prevent catastrophic engine damage.
Spark Plugs:
Replace every 60,000 - 105,000 miles, depending on plug type (Iridium recommended).
Engine Oil:
SAE 5W-30 or 10W-30 (API SG, SH, SJ, SL, SM or ILSAC GF-3, GF-4). Turbocharged models may prefer 5W-30 synthetic.
Coolant:
Subaru Super Coolant (blue) or equivalent ethylene glycol-based antifreeze/coolant with corrosion inhibitors, mixed 50/50 with distilled water.
Transmission Fluid Manual:
GL-4 Gear Oil, SAE 75W-90 (e.g., Subaru Extra-S or equivalent synthetic).
Transmission Fluid Automatic:
Subaru ATF-HP (High Performance) or equivalent DEXRON III/MERCON compatible fluid.
Differential Fluid:
GL-5 Gear Oil, SAE 75W-90 for front and rear differentials (Subaru Extra-S recommended for rear LSD).
Head Gaskets:
While less prevalent than on earlier EJ engines, some EJ253 engines can experience head gasket leaks, particularly coolant leaks from the front of the engine. The manual details diagnostic procedures.
Turbo Failure:
On WRX models, turbocharger failure can occur due to oil starvation or contamination. Proper maintenance and warm-up/cool-down cycles are crucial, as detailed in the manual.
Clutch Wear:
Aggressive driving or heavy towing can accelerate clutch wear. The manual provides clutch inspection and replacement procedures.
Suspension Bushings:
Front and rear suspension bushings can wear over time, leading to clunking noises and degraded handling. The manual shows replacement procedures for these components.
Motorsport Legacy:
Subaru's strong WRC (World Rally Championship) heritage significantly influenced the Impreza's design and performance, particularly the WRX and STI models.
Generation:
Second Generation (2001-2007 GD/GG chassis)
Design Changes:
Significant redesign from the previous generation, moving to the GD/GG platform. Early models (2001-2003) known for 'bug eye' headlights, later refreshed (2004-2005) with 'hawk eye' headlights, and further updated (2006-2007) with 'dog eye' headlights.
Manufacturing Location:
Japan
