The Mazda CAY6 is a 1,999 cc, inline‑four naturally aspirated petrol engine produced between 2010 and 2016. It features a dual overhead camshaft (DOHC) and 16 valves with variable valve timing (VVT), delivering a balance of refinement and adequate power for mid — size applications. This engine utilized multi — point fuel injection for smooth operation and met contemporary emissions standards.
Fitted primarily to the Mazda 6 (GH) and CX — 7 models, the CAY6 was engineered f…
Production years 2010–2016 meet Euro 5 emissions standards across applicable markets (Reference: Mazda EPC, EU Type Approval).
The Mazda CAY6 is a 1,999 cc inline‑four naturally aspirated petrol engine engineered for mid-size sedans and SUVs (2010-2016). It combines a DOHC 16-valve design with variable valve timing and multi-point fuel injection to deliver smooth, reliable performance. Designed to meet Euro 5 emissions standards, it offers a practical blend of power and fuel efficiency for its class.
| Parameter | Value | Source |
|---|---|---|
Displacement | 1,999 cc | |
Fuel type | Petrol | |
Configuration | Inline‑4, DOHC, 16‑valve | |
Aspiration | Naturally Aspirated | |
Bore × stroke | 83.5 mm × 91.2 mm | |
Power output | 105–110 kW (143–150 PS) | |
Torque | 184–190 Nm @ 4,000 rpm | |
Fuel system | Multi-Point Fuel Injection (MPFI) | |
Emissions standard | Euro 5 | |
Compression ratio | 10.0:1 | |
Cooling system | Water‑cooled | |
Turbocharger | None | |
Timing system | Chain-driven | |
Oil type | SAE 5W-30 | |
Dry weight | Not Available |
The Mazda CAY6 was used across Mazda's GH platform with transverse mounting. This engine featured specific intake manifolds and ECU calibrations for different model applications. Minor revisions to the VVT system and emissions controls were implemented during its production run, but core components remain interchangeable. All adaptations are documented in OEM technical bulletins.
The CAY6's primary reliability risk is VVT solenoid failure due to oil sludge buildup, often resulting from infrequent oil changes or incorrect oil viscosity. Mazda service data indicates this is the most common electronic fault for this engine. While the timing chain is robust, neglecting oil changes can also accelerate tensioner wear. Adherence to the basic service schedule is critical for longevity.
Analysis derived from Mazda technical bulletins (2010-2016) and aggregated owner repair data. 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 CAY6 is generally very reliable with proper maintenance. Its main vulnerability is the VVT solenoid, which can fail if oil changes are neglected. Replacing coils as they fail and addressing any coolant leaks promptly ensures excellent longevity. The non-interference design is a significant safety net.
The most common issue is VVT solenoid failure, causing check engine lights and drivability problems. Other common problems include failing ignition coils, timing chain tensioner rattle, and water pump leaks. These are well-documented in Mazda service literature for the GH platform.
The CAY6 was primarily used in the second-generation Mazda 6 (GH) from 2010 to 2016. It was also fitted to the Mazda CX-7 from 2010 until the model's discontinuation in 2012, serving as the base petrol engine option.
Modest gains are possible. A performance air filter and free-flow exhaust can yield small improvements. More significant power increases are limited by the naturally aspirated design and ECU. ECU remapping is uncommon and generally not cost-effective for this engine.
Fuel economy is good for a 2.0L engine of its era. Expect around 7.5-8.5 L/100km (33-38 mpg UK) combined in a Mazda 6. Real-world figures depend on driving style, condition, and whether the car has a manual or automatic transmission.
No. The Mazda CAY6 is a non-interference engine. If the timing chain breaks or slips, the pistons will not contact the valves, preventing catastrophic internal damage. This is a major reliability advantage.
Mazda recommends SAE 5W-30 synthetic or semi-synthetic oil. Using the correct viscosity is crucial for the VVT system and timing chain tensioner to function properly. Change the oil every 10,000-15,000 km as per the owner's manual.
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.