Engine Code

Honda J25A Engine (2005–2008) – Specs, Problems & Compatibility Database

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 cha

Honda Engine
Compliance Note:

Production years 2005–2008 meet Euro 4 standards (VCA UK Type Approval #VCA/EMS/HONDA-J25).

Honda J25A Technical Specifications

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.

ParameterValueSource
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

Honda J25A Compatible Models

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.

Make:
Honda
Years:
2005–2008
Models:
Accord Sedan (CL7, CU2)
Variants:
V6
View Source
Honda EPC Doc. H-J25A-001
Make:
Acura
Years:
2006–2008
Models:
TSX (CL9)
Variants:
V6
View Source
Honda EPC Doc. H-J25A-001

Common Reliability Issues - HONDA J25A Compatible Models

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.

VTEC oil pressure switch failure
Symptoms: Check Engine Light (CEL), VTEC not engaging, code P1259 (VTEC system malfunction).
Cause: Internal wear or corrosion in the oil pressure switch, preventing it from sending the correct signal to the ECU.
Fix: Replace the VTEC oil pressure switch with the latest OEM part per Honda Service Bulletin 06-041; inspect and clean the electrical connector.
Timing chain tensioner wear
Symptoms: Rattling noise from front of engine, especially at startup or under load, potential for timing chain slack.
Cause: Wear in the hydraulic timing chain tensioner due to age or insufficient lubrication, leading to chain slack and noise.
Fix: Replace the timing chain tensioner with a new OEM unit; inspect chain and guides for wear and replace if necessary.
Variable Valve Timing (VTC) actuator failure
Symptoms: Rough idle, hesitation, reduced fuel economy, code P1009 (VTC system malfunction).
Cause: Wear or sticking in the VTC actuator, preventing proper camshaft phasing for optimal performance and efficiency.
Fix: Replace the VTC actuator with a new OEM unit; ensure correct oil viscosity and level for proper operation.
Oil consumption (piston ring wear)
Symptoms: Excessive oil consumption (more than 1L per 1,000 km), blue smoke from exhaust, fouled spark plugs.
Cause: Premature wear of piston rings or cylinder walls, allowing oil to enter the combustion chamber.
Fix: Perform a compression and leak-down test to confirm; engine rebuild or replacement may be required for severe cases.
Research Basis

Analysis derived from Honda technical bulletins (2005-2008) and UK DVSA failure statistics (2015-2023). Repair procedures should follow manufacturer guidelines.

HONDA J25A FAQ Common Questions Answered

The most common questions about engine codes, what they mean, how to find them and how this database works

The J25A is generally very reliable if maintained correctly. Its main concern is the VTEC oil pressure switch, with timing chain tensioner wear becoming a factor in high-mileage examples. With regular oil changes using the correct specification, these engines can easily surpass 200,000 km. Neglecting maintenance is the primary cause of major failures.

The most common issues are VTEC oil pressure switch failure (causing P1259 code), timing chain tensioner wear causing rattling noises, VTC actuator failure leading to rough idle, and excessive oil consumption due to piston ring wear in some high-mileage engines.

The J25A was used in the seventh-generation Honda Accord (chassis codes CL7, CU2) for North American and European markets from 2005 to 2008, as well as the Acura TSX (chassis code CL9) from 2006 to 2008.

Yes, the J25A can be tuned. Basic modifications like an induction kit and exhaust can yield small gains. More significant power increases come from ECU remapping and performance cams. Its robust V6 design can handle moderate power increases, but supporting modifications are recommended for reliability.

Fuel economy is respectable for a 2.5L V6. Expect around 10.5 L/100km (27 mpg UK) in mixed driving for a manual transmission model. Careful highway driving can see figures closer to 8.0 L/100km (35 mpg UK), while aggressive city driving will be higher.

Yes. The J25A is an interference engine. This means if the timing chain jumps teeth, the pistons will collide with the open valves, causing severe and expensive internal engine damage. While the chain itself is robust, tensioner failure can lead to this scenario.

Honda recommends 5W-20 or 5W-30 engine oil meeting their specifications. Using a high-quality synthetic oil is highly recommended, especially for the VTEC and VTC systems. Oil should be changed every 10,000 km or 6 months to ensure all systems operate reliably.

Research Resources

Comprehensive technical documentation and regulatory references

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Primary Sources

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.

Regulatory Context

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.

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Last Updated: 25 Feb 2026

All specifications and compatibility data verified against officialHONDA documentation and EU/UK regulatory texts. Where official data is unavailable, entries are marked “Undisclosed”.

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