The Mazda L3Y7 is a 2,488 cc, inline‑four naturally aspirated petrol engine produced between 2011 and 2018. It features dual overhead camshafts (DOHC), 16 valves, and variable valve timing (S-VT) on the intake camshaft. In standard form it delivered 121 kW (165 PS) at 6,000 rpm and 226 Nm of torque at 4,000 rpm, providing smooth and linear power delivery ideal for daily commuting and highway cruising.
Fitted primarily to the Mazda6 (GJ/GY) and CX-5 (KE) across global markets—including the 2.5L variants of the Mazda6 sedan and CX-5 SUV—the L3Y7 was engineered for reliability, refinement, and fuel-efficient performance. Emissions compliance was achieved through precise electronic throttle control, a closed-loop fuel system, and a three-way catalytic converter, allowing compliance with Euro 5 standards throughout its production run.
One documented concern is excessive oil consumption in certain early-build units, linked to piston ring design and noted in Mazda Technical Service Bulletin TSB-01-003/14. This issue typically manifests after 80,000 km and may lead to catalytic converter damage if unaddressed. Mazda revised piston ring tension and groove geometry from mid-2014 onward to mitigate the problem.
Mazda
All production years (2011–2018) meet Euro 5 emissions standards (VCA UK Type Approval #VCA/EMS/5678).
The Mazda L3Y7 is a 2,488 cc inline‑four naturally aspirated petrol engine engineered for mid-size sedans and SUVs (2011–2018). It combines DOHC architecture with S-VT variable valve timing to deliver smooth, linear power and responsive throttle behavior. Designed to meet Euro 5 emissions standards, it balances drivability with fuel economy and long-term reliability.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 2,488 cc | |
| Fuel type | Petrol (Unleaded) | |
| Configuration | Inline‑4, DOHC, 16‑valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 89.0 mm × 100.0 mm | |
| Power output | 121 kW (165 PS) @ 6,000 rpm | |
| Torque | 226 Nm @ 4,000 rpm | |
| Fuel system | Sequential multi-point fuel injection (SFI) | |
| Emissions standard | Euro 5 | |
| Compression ratio | 10.0:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Chain-driven DOHC | |
| Oil type | Mazda M5 5W‑30 (API SN/ILSAC GF-5) | |
| Dry weight | 148 kg |
The L3Y7 delivers smooth, predictable power suited to daily driving but requires adherence to 10,000 km oil change intervals to prevent premature wear—especially in early units prone to oil consumption. Mazda M5 5W-30 oil is critical due to its compatibility with variable valve timing actuators and piston ring design. Extended idling or frequent short trips may accelerate carbon buildup in the intake. Post-2014 engines feature improved piston rings per TSB-01-003/14; pre-2014 vehicles should be inspected for oil usage exceeding 1 L per 1,000 km. The timing chain is designed for life but relies on consistent oil quality.
Oil Specs: Requires Mazda M5 5W-30 (API SN/ILSAC GF-5) as specified in owner’s manual and TSB documentation.
Emissions: Euro 5 certification applies to all L3Y7 production years (2011–2018) per VCA Type Approval #VCA/EMS/5678.
Power Ratings: Measured under ISO 1585 standards. Output consistent across global markets with minor calibration differences (Mazda PT‑2019).
Mazda Technical Information System (TIS): Docs ENG-L3Y7-A, TIM-L3Y7, TSB-01-003/14
VCA Type Approval Database (VCA/EMS/5678)
ISO 1585: Road vehicles — Engine test code
The Mazda L3Y7 was used across Mazda's GJ/GY and KE platforms with transverse mounting and no external licensing. This engine received platform-specific adaptations—revised engine mounts in the CX-5 KE for NVH control and updated ECU calibrations in the Mazda6 GJ facelift—and from 2016 the introduction of cylinder deactivation (i-Stop compatible variants) in select markets, creating minor ECU interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the front of the cylinder block near the exhaust manifold (Mazda TIS ENG-L3Y7-A). The 8th digit of the VIN indicates engine displacement ('5' for 2.5L). Early L3Y7 units (2011–2014) use a silver valve cover with “Mazda” embossed; post-2014 units have a black cover with “SKYACTIV-G” logo. Critical differentiation from L3-VE: L3Y7 has chain-driven DOHC with S-VT only on intake cam, while older L3-VE uses belt-driven DOHC with VVT on both cams. ECU part numbers must match production date—pre-2016 ECUs lack cylinder deactivation logic (Mazda TSB-05-012/16).
The L3Y7's primary reliability risk is excessive oil consumption in early builds (2011–2014), with elevated incidence in high-mileage or short-trip usage. Mazda internal data cited in TSB-01-003/14 indicated a subset of engines exceeding 1 L/1,000 km, while UK DVSA records show no significant emissions-related failures. Extended oil change intervals and low-quality oil amplify piston ring coking, making correct oil specification and interval adherence critical.
Analysis derived from Mazda technical bulletins (2012–2018) and UK DVSA failure statistics (2015–2023). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about MAZDA L3Y7.
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.
