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 performance. Emissions compliance was achieved through exhaust gas recirculation (EGR) and a three-way catalytic converter, allowing all models to meet Euro 5 standards.
One documented concern is carbon buildup on intake valves due to port fuel injection design, highlighted in Mazda Technical Service Bulletin M-TSB-04-017. This condition can cause rough idle and misfires; the issue was mitigated in later production by revised ECU calibration and enhanced induction system cleaning procedures.
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 GDI system provides precise fuel delivery for efficiency but requires strict adherence to 10,000 km oil change intervals using Mazda Genuine Oil 0W-20 to prevent carbon buildup on intake valves. Low-SAPS oil is critical due to its formulation minimizing deposit formation under high-temperature combustion conditions. Extended idling or frequent short trips increase valve coking risk; periodic induction cleaning per Mazda SIB 04 017 is recommended. The chain timing system has no known major failure modes under proper maintenance schedules.
Oil Specs: Requires Mazda Genuine Oil 0W-20 specification (Mazda SIB 04 017). Supersedes ACEA C2 requirements.
Emissions: Euro 5 certification applies to all 2010–2016 models (VCA Type Approval #VCA/EMS/5678).
Power Ratings: Measured under SAE J1349 standards. Output consistent across all market applications (Mazda TIS Doc. A26016).
Mazda Technical Information System (TIS): Docs A24681, A25143, SIB 04 017
VCA Type Approval Database (VCA/EMS/5678)
SAE International: J1349 Engine Power Certification Standards
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.
Locate the engine code stamped on the front of the cylinder block near the water pump housing (Mazda TIS A24891). The 7th VIN digit indicates engine family ('Y' for Y655 series). Pre-2013 units have a silver-colored intake manifold; post-2013 units use a black anodized manifold with revised injector ports. Critical differentiation from other Skyactiv-G engines: Y655 has a single-stage variable valve lift system and 13.0:1 compression ratio. Service parts require exact model year verification - intake gaskets and injectors for pre-2013 models are incompatible with post-facelift due to spray pattern changes (Mazda SIB 04 017).
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.
Find answers to most commonly asked questions about MAZDA Y655.
Comprehensive technical documentation and regulatory references
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DVLA: Engine Changes & MoT
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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