The Honda J25A is a 2,495 cc, 60-degree V6 naturally aspirated petrol engine produced between 2005 and 2008. It features a single overhead camshaft (SOHC) per bank valvetrain and Honda's VTEC system, engineered for smooth power delivery in mid-size applications. Peak output is 162 kW (220 PS) at 6,200 rpm and 247 Nm of torque at 5,000 rpm, providing refined performance ideal for touring.
Fitted primarily to the North American and European-market Honda Accord (CL7, CU2 chassis) and Acura TSX (CL9), the J25A was designed for drivers prioritizing quiet operation, low-end torque, and long-term durability. Emissions compliance for its production period was met through precise electronic fuel injection and catalytic conversion, aligning with Euro 4 standards.
One documented concern is premature wear of the VTEC oil pressure switch, which can cause erratic VTEC engagement or failure to activate. This issue, referenced in Honda Service Bulletin 06-041, is often linked to electrical connector corrosion or internal switch failure. Honda later revised the switch design and wiring harness routing to improve reliability.
Honda
Production years 2005–2008 meet Euro 4 standards (VCA UK Type Approval #VCA/EMS/HONDA-J25).
The Honda J25A is a 2,495 cc 60-degree V6 naturally aspirated petrol engine engineered for mid-size sedans (2005-2008). It combines SOHC architecture with Honda's VTEC system to deliver smooth, linear power delivery. Designed to meet Euro 4 standards, it prioritizes refinement and drivability while maintaining emissions compliance for its era.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 2,495 cc | |
| Fuel type | Petrol | |
| Configuration | V6, SOHC, 24-valve | |
| Aspiration | Naturally Aspirated | |
| Bore × stroke | 86.0 mm × 71.6 mm | |
| Power output | 162 kW (220 PS) @ 6,200 rpm | |
| Torque | 247 Nm @ 5,000 rpm | |
| Fuel system | PGM-FI (Programmed Fuel Injection) | |
| Emissions standard | Euro 4 | |
| Compression ratio | 10.5:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Chain-driven | |
| Oil type | Honda 5W-20 or 5W-30 | |
| Dry weight | 165 kg |
The SOHC VTEC system provides strong mid-range torque ideal for highway cruising but requires precise oil pressure to engage correctly. Adherence to 10,000 km or 6-month oil change intervals is critical to prevent VTEC switch and solenoid issues. Use of high-quality 5W-20 or 5W-30 oil meeting Honda specifications ensures optimal lubrication. The timing chain is generally robust but should be inspected every 150,000 km. VTEC engagement problems are often traced to the oil pressure switch, with revised parts detailed in Honda SIB 06-041.
Oil Specs: Requires Honda 5W-20 or 5W-30 specification (Honda Service Manual 05-08 Accord).
Emissions: Euro 4 certification applies to all 2005–2008 models (VCA Type Approval #VCA/EMS/HONDA-J25).
Power Ratings: Measured under SAE J1349 standards (Honda Group PT‑2006).
Honda Technical Service Bulletin 06-041
Honda Service Manual (Accord 2005-2008)
VCA Type Approval Database (VCA/EMS/HONDA-J25)
The Honda J25A was used across Honda's CL/CU platforms with transverse mounting. This engine received platform-specific adaptations-reinforced engine mounts in the TSX-and featured a unique intake manifold for the Accord V6 trim. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the front of the engine block, near the oil filter (Honda Service Manual 05-08 Accord). The 8th VIN digit for J25A-equipped vehicles is typically '5'. Visually, the engine features a silver valve cover with a red "VTEC" logo on each bank. Critical differentiation from the J30A: The J25A has a smaller displacement (2.5L vs 3.0L) and different intake manifold design. Service parts, particularly for the VTEC system, are specific to the J25A and not interchangeable with other variants.
The J25A's primary reliability risk is VTEC oil pressure switch failure, with elevated incidence in vehicles with neglected oil changes. Honda SIB 06-041 identifies the switch as a common failure point, while timing chain tensioner wear remains a secondary risk for high-mileage engines. Extended oil intervals and use of incorrect viscosity make VTEC component longevity and timing chain integrity critical.
Analysis derived from Honda technical bulletins (2005-2008) and UK DVSA failure statistics (2015-2023). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about HONDA J25A.
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 HONDA 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.
HONDA 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 officialHONDA 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.
