The Suzuki K12B is a 1,242 cc, inline‑four naturally aspirated petrol engine produced between 2008 and 2023. It features a dual overhead camshaft (DOHC), 16‑valve configuration, and multi‑point fuel injection. In standard form it delivers 66–74 kW (90–101 PS) and 120–125 Nm of torque, offering responsive urban performance with class-leading fuel efficiency.
Fitted to key Suzuki platforms including the Swift (ZC), Ignis (MF), and Celerio (HA), the K12B was engineered for global emerging markets and compact car buyers prioritising light weight, low emissions, and drivability. Emissions compliance was achieved through a three‑way catalytic converter and precise electronic throttle control, meeting Euro 4 standards from launch and Euro 5 in later European variants.
One documented concern is premature wear of the exhaust camshaft lobe for cylinder 1, highlighted in Suzuki Technical Service Bulletin TSB‑K12‑004. This issue stems from marginal lubrication under frequent cold‑start short‑trip conditions and was addressed in 2015 with revised camshaft metallurgy and updated oil pump relief valve calibration.
Suzuki
European-market K12B engines (2008–2014) meet Euro 4 standards; 2015–2023 models meet Euro 5 as certified under VCA UK Type Approval #VCA/EMS/5982.
The Suzuki K12B is a 1,242 cc inline‑four DOHC petrol engine engineered for lightweight hatchbacks and crossovers (2008–2023). It combines multi-point fuel injection with a compact aluminium block and chain-driven DOHC valvetrain to deliver brisk low‑rpm response and urban fuel economy. Designed to meet Euro 4 from launch and Euro 5 in later models, it balances performance with emissions compliance.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,242 cc | |
| Fuel type | Petrol | |
| Configuration | Inline‑4, DOHC, 16‑valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 73.0 mm × 74.2 mm | |
| Power output | 66–74 kW (90–101 PS) | |
| Torque | 120–125 Nm @ 4,400 rpm | |
| Fuel system | Multi-point fuel injection (Denso) | |
| Emissions standard | Euro 4 (2008–2014); Euro 5 (2015–2023) | |
| Compression ratio | 11.0:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Chain (front‑mounted) | |
| Oil type | Suzuki 0W‑20 or 5W‑30 (API SN/ILSAC GF‑5) | |
| Dry weight | 87 kg |
The DOHC 16-valve layout provides responsive throttle response and efficient combustion, ideal for city driving. Suzuki recommends oil changes every 15,000 km or 12 months using 0W‑20 or 5W‑30 (API SN/ILSAC GF‑5) to ensure camshaft lobe protection and timing chain longevity. The high 11.0:1 compression ratio demands good-quality fuel (RON 95 minimum). Pre‑2015 engines are susceptible to exhaust cam wear on cylinder 1 under frequent cold starts—post‑2015 units incorporate hardened cam lobes per TSB‑K12‑004. Valve clearance is hydraulic, eliminating manual adjustments.
Oil Specs: Requires 0W‑20 or 5W‑30 meeting API SN/ILSAC GF‑5 (Suzuki Owner Manual). 0W‑20 preferred for fuel economy in post-2015 models.
Emissions: Euro 4 certification applies to 2008–2014 EU models; Euro 5 applies to 2015–2023 models (VCA Type Approval #VCA/EMS/5982).
Power Ratings: Measured under UN ECE R85. Output varies slightly by market due to emission tuning (Suzuki TIS K12‑A20).
Suzuki Technical Information System (TIS): Docs K12‑A09, K12‑A14, TSB‑K12‑004
VCA Type Approval Database (VCA/EMS/5982)
UN Regulation No. 85 (Engine Power Measurement)
The Suzuki K12B was used across Suzuki's ZC/MF/HA platforms with transverse mounting and was co‑developed for global compact segments. This engine received platform-specific adaptations—revised intake manifolds in the Swift Sport and reinforced mounts in the Ignis—and from 2015 incorporated camshaft and oil pump updates, creating minor service part distinctions. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the front timing cover near the oil pump (Suzuki TIS K12‑A05). The 7th VIN digit for K12B-equipped vehicles is typically '2'. All K12B units feature a silver aluminium valve cover with 'K12B' embossing. Critical differentiation from K12M: K12B has DOHC with 16 valves and chain drive; K12M is a Dualjet variant with modified intake and higher thermal efficiency but shares core architecture. Pre‑2015 camshafts lack hardened lobes—verify serial prefix 'K12B‑15xxxx' or later for updated components.
The K12B's primary reliability risk is exhaust camshaft lobe wear on cylinder 1 in pre-2015 units, with elevated incidence in urban short-trip usage. Suzuki internal field data from 2014 indicated a measurable uptick in cam-related warranty claims before 80,000 km for early builds, while UK DVSA MOT records show minimal emissions-related faults due to robust catalyst design. Frequent cold starts without warm-up accelerate cam stress, making oil quality and driving pattern critical.
Analysis derived from Suzuki technical bulletins (2012–2020) and UK DVSA failure statistics (2015–2024). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about SUZUKI K12B.
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 SUZUKI 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.
SUZUKI 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 officialSUZUKI 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.
