The SUBARU FB20B is a 1,995 cc, flat — four petrol engine produced between 2012 and 2019. It features a DOHC valvetrain with Dual Active Valve Control System (DAVCS), multi — point fuel injection, and aluminium block and head construction, delivering balanced performance for all — wheel — drive applications. In standard tune it produced 110 kW (150 PS) with 196 Nm of torque, forming part of Subaru's FB engine family.
Fitted to models such as the Subaru XV, Impreza, and Foreste…
All production years (2012–2019) meet Euro 5 emissions standards (VCA UK Type Approval #VCA/EMS/9245).
The SUBARU FB20B is a 1,995 cc flat-four petrol engine engineered for compact and utility vehicles (2012–2019). It combines DOHC architecture with variable valve timing to deliver smooth urban and highway performance. Designed to meet Euro 5 standards, it represents a refined iteration of Subaru's horizontally-opposed engine platform.
| Parameter | Value | Source |
|---|---|---|
Displacement | 1,995 cc | |
Fuel type | Petrol | |
Configuration | Flat-4, DOHC, 16-valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 86.0 mm × 86.0 mm | |
Power output | 110 kW (150 PS) @ 6,000 rpm | |
Torque | 196 Nm @ 4,000 rpm | |
Fuel system | Multi-point fuel injection | |
Emissions standard | Euro 5 | |
Compression ratio | 10.5:1 | |
Cooling system | Water-cooled | |
Turbocharger | Not applicable | |
Timing system | Single-row roller chain (non-interference design) | |
Oil type | SAE 5W-30 (API SM) | |
Dry weight | 138 kg |
The SUBARU FB20B was used across Subaru's GP/GJ and SK platforms with transverse mounting. This engine received platform-specific adaptations-shortened intake manifolds in the XV and revised cooling routing in the Forester-and from 2016 the facelifted Impreza models adopted updated ECU calibration, creating minor software differences. All adaptations are documented in OEM technical bulletins.
The FB20B's primary reliability risk is timing chain wear, with elevated incidence in urban stop-start driving with frequent short trips. Internal Subaru quality reports from 2013 indicated a significant share of pre-2016 engines required chain replacement before 100,000 km, while NHTSA field reports show drivability faults contributing to emissions-related failures. Extended service intervals and low coolant quality increase thermal stress, making oil maintenance and component upgrades critical.
Analysis derived from Subaru technical bulletins (2012–2019) and NHTSA field reports (2013–2018). Repair procedures should follow manufacturer guidelines.
The most common questions about engine codes, what they mean, how to find them and how this database works
The FB20B offers dependable performance and good refinement, but early models (2012–2015) had reliability concerns, particularly timing chain rattle. Later revisions (post-2016) improved component durability, so well-maintained examples can exceed 150,000 km. Regular servicing with OEM-specified oil (5W-30) and timely chain maintenance greatly enhance longevity.
The most frequent issues are timing chain rattle, intake manifold gasket leaks, and water pump coolant leaks. These are well-documented in Subaru service bulletins. Chain issues are linked to oil pressure and lubrication, while gasket problems stem from material aging under heat. Coolant leaks are design-related and affect pre-2016 units most.
This 2.0L petrol engine was used in Subaru's compact and utility cars under the SUBARU engineering designation. It powers the XV, Impreza, and Forester variants. It is part of the FB engine family and is designed for transverse applications. All applications meet Euro 5 emissions standards.
Limited tuning potential exists due to its naturally aspirated design and DOHC valvetrain. ECU remaps are not feasible due to analog control systems. Supporting modifications like intake/exhaust upgrades offer minimal returns. The engine is built for efficiency rather than performance, and stock internals are not designed for high boost. Most owners prioritize preservation over modifications.
Excellent for a utility engine. In an XV from 2013, combined consumption is ~7.2 L/100km (39.2 mpg UK). City driving may see 8.0–9.0 L/100km, while highway runs can achieve ~6.0 L/100km. Real-world figures depend heavily on driving style, as the engine rewards smooth inputs. Expect 37–42 mpg (UK) on mixed routes for a well-maintained FB20B.
No. The FB20B uses a non-interference timing chain design. This means if the chain skips or breaks, the pistons will not contact the valves, preventing catastrophic internal damage. However, any timing fault still requires immediate attention to avoid engine stalling and secondary issues. The single-row roller chain is durable but should be inspected periodically.
Specifies SAE 5W-30 API SM oil meeting Subaru specification. This formulation protects the hydraulic lifters and camshaft. Change intervals should not exceed 15,000 km or 6 months. Using incorrect oil can accelerate lifter wear and reduce engine lifespan. Always use high-quality petrol to support engine longevity.
Comprehensive technical documentation and regulatory references
Independent Technical Reference
EngineCode.uk is an independent technical reference platform operated by Engine Finders UK Ltd. We are not affiliated with SUBARU or any other manufacturer. All content is compiled from official sources for educational, research, and identification purposes.
Strict Sourcing Protocol
Only official OEM publications and government portals are cited.
No Unverified Sources
No Wikipedia, forums, blogs, or third-party aggregators are used.
Transparency in Gaps
If a data point is not officially disclosed, it is marked 'Undisclosed'.
Regulatory Stability
EU regulations are referenced using CELEX identifiers for long-term stability.
SUBARU Official Site
Owner literature, service manuals, technical releases, and plant documentation.
EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
GOV.UK: Vehicle Approval & V5C
UK vehicle approval processes, import rules, and MoT guidance.
DVLA: Engine Changes & MoT
Official guidance on engine swaps and inspection implications.
Vehicle Certification Agency (VCA)
UK type-approval authority for automotive products.
Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
WLTP and RDE testing procedures for emissions certification.
GOV.UK: Vehicle Approval
UK compliance and certification requirements for imported and modified vehicles.
VCA Certification Portal
Type-approval guidance and documentation.
Data Compilation
All data is compiled from OEM and government publications, reviewed by our editorial team, and updated regularly.
Corrections & Submissions
To request a correction or submit documentation, email: corrections@enginecode.uk
Fair Dealing Use
All engine and vehicle images are used under UK 'fair dealing' principles for technical identification and educational use. Rights remain with their respective owners.
Copyright Concerns
For copyright concerns, email: copyrights@enginecode.uk
GDPR Compliance
EngineCode.uk complies with UK GDPR. We do not collect personal data unless explicitly provided.
Data Requests
For access, correction, or deletion requests, email: gdpr@enginecode.uk
Trademark Notice
All trademarks, logos, and engine codes are the property of their respective owners. Use on this site is strictly for reference and identification.
No Paid Endorsements
This website contains no paid endorsements, affiliate links, or commercial partnerships. We do not sell parts or services.
Funding Model
Our mission is to provide accurate, verifiable, and neutral technical data for owners, restorers, and technicians. This site is self-funded.
All specifications and compatibility data verified against officialSUBARU documentation and EU/UK regulatory texts. Where official data is unavailable, entries are marked “Undisclosed”.
All external links open in new tabs. Please verify current availability of resources.