The Honda F23A1 is a 2,254 cc, inline‑four naturally aspirated petrol engine produced between 1998 and 2002. It features a single overhead camshaft (SOHC) valvetrain and Honda's VTEC system, engineered for refined torque and reliability in mid-size applications. Peak output is 150 PS (110 kW) at 5,700 rpm and 206 Nm of torque at 4,900 rpm, delivering smooth, linear power ideal for touring.
Fitted primarily to the North American and European-market Honda Accord (CG7, CH6 chassis) and Acura CL (UA2), the F23A1 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 2 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 99-056, 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 1998–2002 meet Euro 2 standards (VCA UK Type Approval #VCA/EMS/HONDA-F23).
The Honda F23A1 is a 2,254 cc inline‑four naturally aspirated petrol engine engineered for mid-size sedans and coupes (1998-2002). It combines SOHC architecture with Honda's VTEC system to deliver smooth, torque-rich performance. Designed to meet Euro 2 standards, it prioritizes refinement and drivability while maintaining emissions compliance for its era.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 2,254 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) @ 5,700 rpm | |
| Torque | 206 Nm @ 4,900 rpm | |
| Fuel system | PGM-FI (Programmed Fuel Injection) | |
| Emissions standard | Euro 2 | |
| Compression ratio | 9.3:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Belt-driven | |
| Oil type | Honda 5W-30 or 10W-40 | |
| Dry weight | 155 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-30 oil meeting Honda specifications ensures optimal lubrication. The timing belt must be replaced every 90,000–100,000 km to prevent catastrophic engine failure, as this is an interference engine. VTEC engagement problems are often traced to the oil pressure switch, with revised parts detailed in Honda SIB 99-056.
Oil Specs: Requires Honda 5W-30 or 10W-40 specification (Honda Service Manual 98-02 Accord).
Emissions: Euro 2 certification applies to all 1998–2002 models (VCA Type Approval #VCA/EMS/HONDA-F23).
Power Ratings: Measured under SAE J1349 standards (Honda Group PT‑1999).
Honda Technical Service Bulletin 99-056
Honda Service Manual (Accord 1998-2002)
VCA Type Approval Database (VCA/EMS/HONDA-F23)
The Honda F23A1 was used across Honda's CG/CH/UA platforms with transverse mounting. This engine received platform-specific adaptations-reinforced engine mounts in the Acura CL-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, just below the exhaust manifold (Honda Service Manual 98-02 Accord). The 8th VIN digit for F23A1-equipped vehicles is typically '3'. Visually, the engine features a silver valve cover with a red "VTEC" logo. Critical differentiation from the non-VTEC F22B: The F23A1 has a VTEC solenoid and oil pressure switch on the rear of the cylinder head. Service parts, particularly for the VTEC system, are specific to the F23A1 and not interchangeable with other variants.
The F23A1's primary reliability risk is VTEC oil pressure switch failure, with elevated incidence in vehicles with neglected oil changes. Honda SIB 99-056 identifies the switch as a common failure point, while timing belt neglect remains a critical risk for all interference engines. Extended oil intervals and use of incorrect viscosity make VTEC component longevity and timing belt integrity critical.
Analysis derived from Honda technical bulletins (1998-2002) and UK DVSA failure statistics (2015-2023). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about HONDA F23A1.
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Regulation (EC) No 715/2007
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