🏷️ Basic Information

Make:

Subaru

Model:

Impreza

Year:

2009

Applicable Chassis Codes:

GE*****, GH*****

Engine Codes:

H4SO, H4DOTC

👋 Introduction

Segment:

Compact car, often positioned as a practical and capable all-wheel-drive option.

Key Competitors 2009:

Honda Civic, Toyota Corolla, Mazda3, Ford Focus, Mitsubishi Lancer.

Standard AWD:

Subaru's symmetrical All-Wheel Drive system is a hallmark feature, offering enhanced traction and stability.

Horizontally Opposed Engine:

Standard horizontally-opposed (Boxer) engine layout for a lower center of gravity and improved handling.

Sporty Variants:

Available in sedan and hatchback body styles, with performance-oriented WRX and STI variants in other model years (though 2009 might be the generation leading into those).

📋 Manual Details

General:

Comprehensive coverage for the 2009 Subaru Impreza.

Engine H4So:

Detailed diagnostics and repair for the H4SO engine variant.

Engine H4Dotc:

Detailed diagnostics and repair for the H4DOTC engine variant.

Transmission:

Service and repair information for the transmission system.

Chassis:

Covers chassis components, suspension, steering, and brakes.

Body:

Includes bodywork, interior trim, and exterior components.

Wiring:

Extensive wiring diagrams and electrical system diagnostics.

Estimated Pages:

Likely over 2000 pages (typical for a complete factory service manual).

Type:

Factory Service Workshop Repair Manual

Language:

English

Format:

PDF Download

📖 Manual Coverage

Engine Mechanical:

Engine assembly, disassembly, timing, cylinder head, piston, crankshaft, lubrication system, cooling system, fuel system (delivery, injection, evaporative emissions).

Engine Performance:

Engine control system (ECM), ignition system, emission control systems, turbocharger (if applicable to specific H4DOTC variant).

Transmission Manual:

Manual transmission disassembly, assembly, clutch operation, gear shifting mechanisms.

Transmission Automatic:

Automatic transmission disassembly, assembly, valve body, torque converter, transmission control module (TCM).

Drivetrain:

All-Wheel Drive (AWD) system, front and rear differentials, driveshafts, CV joints.

Suspension:

Front and rear suspension components, struts, shock absorbers, control arms, sway bars, wheel alignment specifications.

Steering:

Power steering system (hydraulic or electric), steering column, tie rods, steering rack.

Brakes:

Brake system components (discs, pads, calipers, master cylinder, ABS system, brake lines), parking brake.

Electrical Powertrain:

Starter motor, alternator, battery, charging system, engine sensors and actuators.

Electrical Body:

Lighting system (headlights, taillights, interior), power windows, power locks, mirrors, wipers, horn, interior electronics, comfort features.

Climate Control:

HVAC system, A/C compressor, evaporator, condenser, heater core, climate control module.

Safety Systems:

Airbag system, SRS module, seat belt pre-tensioners, ABS, Traction Control System (TCS), Vehicle Dynamics Control (VDC).

Infotainment:

Audio system, navigation system (if equipped), display units, connectivity modules.

Routine Maintenance:

Oil changes, filter replacements, fluid checks and changes, spark plug replacement, air filter replacement.

Diagnostic Troubleshooting:

Step-by-step diagnostic procedures for various fault conditions, DTC (Diagnostic Trouble Code) interpretation and resolution.

Component Replacement:

Detailed instructions for replacing major and minor components across all systems.

Engine Rebuild:

Complete engine disassembly, inspection, repair, and reassembly procedures.

Transmission Overhaul:

Detailed procedures for overhauling both manual and automatic transmissions.

Electrical Repair:

Wiring harness repair, connector diagnostics, component testing, module programming (if applicable).

Body Repair:

Panel replacement, dent repair, corrosion prevention, interior trim removal and installation.

Suspension Alignment:

Wheel alignment procedures and specifications.

Brake Bleeding:

Brake bleeding procedures for ABS and non-ABS systems.

Depth:

Comprehensive from basic maintenance to advanced diagnostics and complete rebuilds. Covers factory-level repair and troubleshooting.

📊 Manual Specifications

Format:

PDF (Portable Document Format)

Searchable:

Typically text-searchable within the PDF document.

Quality:

High-resolution digital format suitable for printing specific sections or the entire manual.

Binding:

Not Applicable (Digital PDF)

Paper Type:

Not Applicable (Digital PDF)

⚙️ Engine Specifications

Engine Type:

2.5L SOHC Naturally Aspirated Flat-4 (Boxer)

Displacement:

2457 cc (2.5 Liters)

Bore X Stroke:

99.5 mm x 79.0 mm

Compression Ratio:

9.7:1

Horsepower Est:

170 hp @ 5800 rpm

Torque Est:

170 lb-ft @ 4400 rpm

Engine Type:

2.5L DOHC Turbocharged Flat-4 (Boxer)

Displacement:

2457 cc (2.5 Liters)

Compression Ratio:

8.4:1

Horsepower Est:

224 hp @ 5200 rpm (WRX variant)

Torque Est:

226 lb-ft @ 2800 rpm (WRX variant)

Induction:

Sequential Multi-Port Fuel Injection (MPI) for H4SO; Sequential Electronic Fuel Injection (EFI) with Turbocharging for H4DOTC.

Fuel Type:

Unleaded gasoline (87 octane recommended for H4SO, 91 octane or higher recommended for H4DOTC).

🔧 Transmission

Transmission Type:

5-speed Manual Transmission (standard on many trims).

Transmission Type:

4-speed Automatic Transmission (optional on many trims).

AWD System:

Subaru's Symmetrical All-Wheel Drive with front/rear or center differential depending on transmission type.

📐 Dimensions

Length:

Approx. 179.5 inches

Width:

Approx. 69.1 inches

Height:

Approx. 58.1 inches

Length:

Approx. 173.8 inches

Width:

Approx. 69.1 inches

Height:

Approx. 58.1 inches

Curb Weight Est:

Approx. 3100 - 3300 lbs (depending on trim and transmission).

Wheelbase:

Approx. 103.1 inches

Ground Clearance:

Approx. 5.7 inches

🛡️ Safety Features

NHTSA Front Impact Driver:

5 Stars

NHTSA Front Impact Passenger:

5 Stars

NHTSA Side Impact Front Seat Passenger:

5 Stars

NHTSA Side Impact Rear Seat Passenger:

5 Stars

IIHS Front Offset Good:

Good

IIHS Side Impact Good:

Good

IIHS Rear Impact Good:

Good

ABS:

Standard Anti-lock Braking System (ABS).

Traction Control:

Standard Traction Control System (TCS).

Stability Control:

Standard Vehicle Dynamics Control (VDC).

Airbags:

Front airbags, front side-impact airbags, side-curtain airbags (standard on most trims).

Seatbelts:

3-point seatbelts with pre-tensioners and force limiters.

💡 Technology Features

Audio System:

Factory-installed AM/FM/CD/MP3 audio systems with available auxiliary input. Higher trims may feature premium audio systems.

Navigation:

Optional GPS navigation system available on select trims, often integrated into the dashboard display.

ABS Esp:

Standard ABS, TCS, and VDC systems contribute to active safety.

Bluetooth:

Optional Bluetooth hands-free connectivity may be available on higher trim levels.

Cruise Control:

Standard cruise control system.

🔧 Maintenance

Oil Change Interval:

Every 3,750 miles or 6 months for severe driving conditions, or 7,500 miles or 12 months for normal driving conditions (refer to manual for specific details).

Air Filter Replacement:

Every 15,000 miles or 12 months, or as needed based on driving environment.

Cabin Air Filter Replacement:

Every 15,000 miles or 12 months, or as needed.

Spark Plug Replacement:

Typically around 60,000 miles for iridium-tipped spark plugs (refer to manual for specific plug type and interval).

Coolant Replacement:

Initial change at 30,000 miles or 48 months, then every 30,000 miles or 24 months thereafter (Subaru Super Coolant).

Transmission Fluid Change:

Manual: Inspect at 30,000 miles, typically not a scheduled replacement. Automatic: Inspect at 30,000 miles, service as needed based on driving; some sources suggest every 60,000 miles.

Engine Oil Type H4So:

SAE 0W-20 Synthetic (API SN or ILSAC GF-5 compliant).

Engine Oil Type H4Dotc:

SAE 5W-30 Synthetic (API SN or ILSAC GF-5 compliant).

Engine Oil Capacity:

Approx. 4.8 US quarts (4.6 L) with filter for 2.5L engines.

Coolant Type:

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

Transmission Fluid Manual:

SAE 75W-90 GL-5 Gear Oil (Subaru Extra-S recommended).

Transmission Fluid Automatic:

Subaru ATF-HP (High Performance) or equivalent.

Differential Fluid Front:

SAE 75W-90 GL-5 Gear Oil.

Differential Fluid Rear:

SAE 75W-90 GL-5 Gear Oil.

Brake Fluid Type:

DOT 3 or DOT 4 brake fluid.

Head Gasket Leaks:

While less prevalent than on earlier generations, internal or external coolant leaks related to head gaskets can still occur, particularly on higher mileage H4SO engines. The manual will guide diagnosis.

Turbocharger Issues H4Dotc:

For the H4DOTC (WRX), turbocharger health and oil supply are critical. Issues can include bearing failure or wastegate problems. The manual provides specific diagnostic steps.

Catalytic Converter Failure:

Can occur due to rich fuel mixtures or oil consumption, impacting emissions. The manual covers diagnostics and replacement.

Clutch Wear:

As with any manual transmission, clutch wear is dependent on driving style and can require replacement. Manual covers clutch inspection and replacement.

Suspension Wear:

Components like bushings and sway bar links may wear over time, affecting handling and ride quality. The manual details inspection and replacement of suspension parts.

📚 Vehicle History

Subaru Heritage:

Subaru, a division of Subaru Corporation (formerly Fuji Heavy Industries), has a long history of producing reliable vehicles, with a strong emphasis on All-Wheel Drive technology and a distinct boxer engine design.

Impreza Generations:

The 2009 model year represents the second generation (GH/GE/GR/GV) of the Subaru Impreza, which debuted for the 2008 model year. This generation marked a significant design shift towards a more 'eagle-eyed' appearance and offered both sedan and hatchback variants. The iconic WRX and STI performance variants were also available.

Manufacturing Locations:

Primarily manufactured in Gunma, Japan. Some assembly may have occurred in other Subaru global facilities.

🏆 Awards & Recognition

IIHS Top Safety Pick:

The 2009 Impreza (GH chassis) received an IIHS Top Safety Pick award for its strong performance in crash tests.

Consumer Reports Reliability:

Reliability ratings for the 2009 Impreza generally fall within the average to above-average range, depending on specific model year and engine configuration. The manual is essential for addressing potential issues proactively.