The Honda H23A2 is a 2,259 cc, inline‑four petrol engine produced between 1998 and 2001. It features a single overhead camshaft (SOHC), 16‑valve valvetrain and programmed fuel injection (PGM‑FI). This engine was designed for refined, torquey performance in Honda's premium models, producing 110 kW (150 PS) and 211 Nm of torque, offering smooth and responsive driving characteristics.
Fitted primarily to the sixth‑generation Honda Accord (CF chassis) Type R and the sec…
Production years 1998–2001 meet Euro 2 standards as per applicable EU regulations for vehicles of that era (VCA UK Type Approval #VCA/EMS/6792).
The Honda H23A2 is a 2,259 cc inline‑four petrol engine engineered for premium compact coupes and sedans (1998-2001). It combines SOHC 16-valve architecture with programmed fuel injection to deliver high torque and responsive performance. Designed to meet Euro 2 emissions standards, it balances sporty character with refined operation.
| Parameter | Value | Source |
|---|---|---|
Displacement | 2,259 cc | |
Fuel type | Petrol | |
Configuration | Inline‑4, SOHC, 16‑valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 86.0 mm × 97.0 mm | |
Power output | 110 kW (150 PS) @ 6,000 rpm | |
Torque | 211 Nm @ 5,000 rpm | |
Fuel system | Programmed Fuel Injection (PGM‑FI) | |
Emissions standard | Euro 2 | |
Compression ratio | 10.0:1 | |
Cooling system | Water‑cooled | |
Turbocharger | None | |
Timing system | Belt-driven | |
Oil type | API SJ/SL, SAE 5W-30 or 10W-30 | |
Dry weight | 138 kg |
The Honda H23A2 was used across Honda's CF platform with transverse mounting. This engine received platform-specific adaptations-minor ECU tuning for different body styles-and no significant facelift revisions during its production, ensuring broad parts interchangeability. All adaptations are documented in OEM technical bulletins.
The H23A2's primary reliability risk is exhaust manifold cracking due to thermal stress, with elevated incidence in spirited driving. Honda Service Bulletin 99-018 documents this as a common cause of exhaust leaks, while UK DVSA data shows emissions-related faults as a frequent MOT advisory for this generation. Adherence to proper warm-up/cool-down cycles and proactive manifold inspection make preventative maintenance critical.
Analysis derived from Honda technical bulletins (1998-2001) and UK DVSA failure statistics (2010-2023). 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
Yes, the H23A2 is a fundamentally robust and reliable engine. Its main weakness is the exhaust manifold, which is prone to cracking under spirited use. With regular maintenance, especially timely timing belt changes and addressing manifold issues, these engines can easily surpass 250,000 km without major problems.
The most frequent issues are exhaust manifold cracks, distributor (ignition coil) failure, and timing belt wear. Valve cover gasket leaks are also common on higher-mileage engines. All these are well-documented in Honda service literature and are relatively inexpensive to fix.
The H23A2 was used in the sixth-generation Honda Accord (CF chassis, 1998-2001) Type R sedan and the fifth-generation Honda Prelude (BB chassis, 1998-2001) Type S coupe. It was a higher-performance variant of the standard H-series engine.
Modest gains are possible. Basic modifications include a cold air intake, performance exhaust, and ignition system upgrade. For significant power, a head swap to a DOHC VTEC head is possible but complex and requires an ECU swap. The stock ECU cannot be remapped.
Good for its performance. Expect around 9.5-10.0 L/100km (28-30 mpg UK) in combined driving for a manual transmission Accord Type R. Highway cruising can return figures closer to 7.0 L/100km (40 mpg UK). Performance driving will significantly reduce economy.
Yes. This is critically important. If the timing belt breaks or jumps time, the pistons will collide with the open valves, causing severe and expensive engine damage. This makes adhering to the 100,000 km replacement interval non-negotiable.
Honda recommends an API SJ or SL specification oil. The viscosity should be SAE 10W-30 for normal conditions, or 5W-30 for colder climates. Using a high-quality synthetic or semi-synthetic oil is beneficial for engine longevity and protection.
Comprehensive technical documentation and regulatory references
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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