Covers Subaru boxer petrol and hybrid engines used across UK and European models - from early EA series to modern FB, FA, and CB turbocharged units. Each engine code includes specifications, compatible vehicles, and emissions data, sourced from official Subaru and EU records.
Data sourced from Subaru Corporation Technical Service Information, EU Regulation (EC) No 715/2007, and Subaru Owner's Manual and Service Documentation.
Find Subaru engine codes by family, model, or generation
| Engine Code | Fuel Type | Series | Specifications |
|---|---|---|---|
| Petrol | CB-Series | View Specs | |
| Petrol | E-Series | View Specs | |
| Petrol | E-Series | View Specs | |
| Petrol | E-Series | View Specs | |
| Petrol | EA-Series | View Specs | |
| Petrol | EA-Series | View Specs | |
| Petrol | EA-Series | View Specs | |
| Petrol | EF-Series | View Specs | |
| Petrol | EF-Series | View Specs | |
| Petrol | EF-Series | View Specs | |
| Petrol | EF-Series | View Specs | |
| Petrol | EG-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EJ-Series | View Specs | |
| Petrol | EL-Series | View Specs | |
| Petrol | EZ-Series | View Specs | |
| Petrol | EZ-Series | View Specs | |
| Petrol | FA-Series | View Specs | |
| Petrol | FA-Series | View Specs | |
| Petrol | FA-Series | View Specs | |
| Petrol | FB-Series | View Specs | |
| Petrol | FB-Series | View Specs | |
| Petrol | FB-Series | View Specs | |
| Petrol | FB-Series | View Specs | |
| Petrol | FB-Series | View Specs | |
| Petrol | FB-Series | View Specs | |
| Petrol | FB-Series | View Specs | |
| Petrol | FB-Series | View Specs | |
| Electric | SOLTERRA-Series | View Specs | |
| Electric | SOLTERRA-Series | View Specs | |
| Petrol | STI-Series | View Specs |
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Engine specifications and technical data sourced from Subaru Corporation Technical Documentation and EU Vehicle Type Approval Database. Consult vehicle documentation or professional guidance before undertaking mechanical work. Report errors or omissions through our contact channels.
Engine Finders UK Ltd, which operates EngineCode.uk, can pass your enquiry to engine suppliers in the UK. The service is for vehicles in the United Kingdom, with UK delivery or fitting. This is a commercially connected service, and sending an enquiry does not confirm diagnosis or compatibility.
The engine code is essential for ordering parts, diagnosing issues, and verifying compatibility. It is not the same as the VIN or chassis number. This guide shows exactly where to find it - by model and engine type - using official Subaru and DVLA sources
A unique identifier stamped on the engine block or valve cover used for parts and service.
The vehicle identification number that holds encoded vehicle and engine information.
The chassis or frame number used for registration and legal identification.
Locate the engine code on the front timing cover (EJ25) or on a white label attached to the valve cover, passenger side (FB25). It is stamped into the metal or printed on the label near the camshaft housing.
The engine code is located on the front left timing cover, near the camshaft housing. Look for "EJ255" (WRX) or "EJ257" (STI) stamped into the aluminium casting.
Open the bonnet and look at the passenger side valve cover. The code is on a white label reading "FB20D" for petrol or "FB20X" for e-BOXER hybrid variants. Confirm with V5C if uncertain.
The engine code is stamped on the front of the block near the oil filter housing. Look for "FA20D" (2012–2020) or "FA24D" (2022+). Also check the valve cover label for confirmation.
Engine code locations per Subaru Service Manual – Vehicle Identification Section. V5C field definitions from DVLA Guide to Vehicle Registration. VIN structure compliant with EU Regulation (EC) No 715/2007, Article 7.
A technical breakdown of Subaru's core boxer engine systems including AVCS, turbocharging architectures, timing belt/chain systems and modular FB/FA design with documented reliability impacts. All data sourced from Subaru Corporation Technical Service Information and EU Regulation (EC) No 715/2007
Subaru's proprietary AVCS system continuously adjusts intake camshaft timing via oil pressure actuators to optimise valve overlap, improving low-end torque, fuel efficiency, and emissions compliance across the rev range.
An oil control valve directs pressurised oil to a camshaft phaser, rotating the cam relative to the sprocket. Dual-AVCS (on FA/FB turbo engines) controls both intake and exhaust cams independently for finer control.
EJ204 (1998)
Intake-only variable timing
EJ255 (2005)
Refined oil control, wider adjustment range
FA24F (2019)
Independent intake/exhaust control
FB25D (2017)
Integrated with direct injection
Oil control valve clogging
especially with extended oil change intervals
Cam phaser wear
rattle on cold start, fault code P0011/P0014
Oil pressure sensitivity
low oil level can disable AVCS function
Subaru's proprietary AVCS system continuously adjusts intake camshaft timing via oil pressure actuators to optimise valve overlap, improving low-end torque, fuel efficiency, and emissions compliance across the rev range.
An oil control valve directs pressurised oil to a camshaft phaser, rotating the cam relative to the sprocket. Dual-AVCS (on FA/FB turbo engines) controls both intake and exhaust cams independently for finer control.
EJ204 (1998)
Intake-only variable timing
EJ255 (2005)
Refined oil control, wider adjustment range
FA24F (2019)
Independent intake/exhaust control
FB25D (2017)
Integrated with direct injection
Oil control valve clogging
especially with extended oil change intervals
Cam phaser wear
rattle on cold start, fault code P0011/P0014
Oil pressure sensitivity
low oil level can disable AVCS function
All technical descriptions and failure data sourced from Subaru Corporation Product Technical Reports, Subaru TIS Service Information, and EU Regulation (EC) No 715/2007 on vehicle type-approval.
Authoritative data on Subaru's global engine production, plant operations, and strategic partnerships. All figures sourced from Subaru Corporation Annual Reports, Sustainability Reports, and EU industrial compliance records.
Subaru manufactures boxer engines at two primary facilities, each specialising in specific families.
Subaru produces approximately 380,000 boxer engines per year. Note the steady growth in hybrid integration (e-BOXER) while maintaining 100% petrol/hybrid powertrains (no diesel for UK/EU markets).
Note: Subaru does not produce diesel engines for UK/EU markets. Hybrid integration rising via e-BOXER and PHEV variants aligned with EU emissions policy.
Strategic collaboration since 2005. FA20D/FA24D boxer engines power the Toyota 86/GR86 sports cars, utilising Subaru's Gunma-built blocks with Toyota calibration.
Boxer layout, direct injection, Dual-AVCS integration
FA20D/FA24D blocks built in Gunma, calibrated by both brands
Subaru Corporation Strategic Partnerships – Toyota Collaboration
Shift in production reflects EU emissions policy and changing consumer demand.
This aligns with Commission Regulation (EU) 2017/1151 (WLTP/RDE) and EU 2035 ICE phase-out roadmap.
Engine production years verified via Subaru Corporation Product Reports and EU type-approval records
The most common questions about engine codes, what they mean, how to find them and how this database works
Confirm the full engine designation using vehicle-specific manufacturer records and the engine marking. An engine serial number, a registration record and a marketed power badge are not automatically the same identifier. Match the VIN/build data and the installed engine before selecting parts or a replacement.
No. A factory-application reference and a replacement-interchange decision are different. Match the full engine designation, vehicle build data, emissions equipment, controls and relevant supplier/OEM information.
No. Records have different review states. Read the correction notice, source scope and application limits on the individual record. Missing technical fields must not be inferred from similar engine codes.
EngineCode.uk provides reference information about Subaru engines. It is operated by Engine Finders UK Ltd and also offers an optional replacement-engine enquiry service. Technical information can contain errors or omissions. Check the sources and verification notes for the relevant record, and confirm the details for your vehicle before buying parts or arranging work.
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