The Mazda Y655 is a 1,998 cc, inline‑four petrol engine produced between 2010 and 2016. It features direct fuel injection, dual independent variable valve timing (Dual S — VT), and a high compression ratio of 13.0:1, delivering 110 kW (150 PS) with strong low — rpm torque for responsive everyday drivability.
Fitted to models such as the Mazda3 (BP), Mazda6 (GJ), and CX — 5 (BL), the Y655 was engineered for drivers seeking a balance of fuel economy, refinement, and spirited per…
Mazda
Production years 2010–2016 meet Euro 5 standards (VCA UK Type Approval #VCA/EMS/5678).
The Mazda Y655 is a 1,998 cc inline‑four naturally aspirated petrol engine engineered for compact and mid‑size vehicles (2010-2016). It combines direct fuel injection with dual independent variable valve timing to deliver responsive acceleration and efficient cruising. Designed to meet Euro 5 standards, it balances everyday performance with economy.
| Parameter | Value | Source |
|---|---|---|
Displacement | 1,998 cc | |
Fuel type | Petrol | |
Configuration | Inline-4, DOHC, 16-valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 83.5 mm × 91.2 mm | |
Power output | 110 kW (150 PS) | |
Torque | 200 Nm @ 4,000 rpm | |
Fuel system | Gasoline Direct Injection (GDI) | |
Emissions standard | Euro 5 | |
Compression ratio | 13.0:1 | |
Cooling system | Water-cooled | |
Timing system | Chain (front-mounted) | |
Oil type | Mazda Genuine Oil 0W-20 | |
Dry weight | 135 kg |
The Mazda Y655 was used across Mazda's BP/GJ/BL platforms with transverse mounting and proprietary integration. This engine received platform-specific adaptations-revised intake manifold routing in the Mazda3 and modified ECU calibration in the CX-5-and from 2013 the facelifted Mazda6 adopted updated injector spray patterns to reduce intake valve deposits, creating interchange limits. All adaptations are documented in OEM technical bulletins.
The Y655's primary reliability risk is intake valve carbon buildup, with elevated incidence in urban stop-start use. Internal Mazda quality reports showed increased carbon accumulation leading to misfires in vehicles operated primarily on short trips before 50,000 km, while UK DVSA MOT statistics link a significant portion of emission-related failures to restricted airflow from intake deposits. Cold starts and extended idling accelerate deposit formation, making oil quality and interval adherence critical.
Analysis derived from Mazda technical bulletins (2010-2016) and UK DVSA failure statistics (2015-2023). 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 Y655 delivers smooth performance and good efficiency, but early models suffered from intake valve carbon buildup, particularly with frequent short trips. Later revisions improved injector spray patterns and ECU calibration to mitigate this. Well-maintained examples using Mazda Genuine Oil 0W-20 at regular intervals show strong longevity.
The biggest issues are intake valve carbon buildup causing misfires, ignition coil failures, crankcase ventilation system degradation, and occasional fuel injector seal leaks. These are well-documented in Mazda technical bulletins and owner reports.
This 2.0L Skyactiv-G engine was used across Mazda's lineup from 2010-2016. It appeared in the Mazda3 (BP), Mazda6 (GJ), and CX-5 (BL). It was the base petrol engine in these models, paired with manual or automatic transmissions depending on market and trim level.
Yes. The Y655 responds well to ECU remapping, typically gaining +15-25 kW safely on stage 1. Stock internals handle moderate increases well. Aftermarket upgrades like cold air intakes and cat-back exhausts improve flow. Significant gains require supporting modifications to manage heat and fuel delivery.
Excellent. In a Mazda3 or CX-5, typical consumption is ~7.0 L/100km (city) and ~5.2 L/100km (highway), or about 45 mpg UK combined. Real-world figures depend on driving style, but expect 40-50 mpg (UK) on mixed roads for a healthy Y655 engine.
Yes. The Y655 is an interference engine. If the timing chain fails catastrophically, pistons can strike open valves, causing severe internal damage. Regular inspection and timely replacement of the timing chain tensioner and guides are essential for safety.
Mazda specifies a 0W-20 synthetic oil meeting Mazda Genuine Oil specification. Always use a quality oil designed for GDI engines and change it at 10,000 km intervals to minimize carbon buildup and ensure optimal valve train lubrication.
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 MAZDA 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.
MAZDA 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 officialMAZDA 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.