The Honda A20A2 is a 1,956 cc, inline‑four naturally aspirated petrol engine produced between 1986 and 1989. It features a single overhead camshaft (SOHC) with 12 valves and Honda's PGM-FI electronic fuel injection system. This design prioritized smooth power delivery and fuel efficiency for its era, producing 86 kW (117 PS) and 162 Nm of torque.
Fitted primarily to the third-generation Honda Accord (CA series) and Vigor models, the A20A2 was engineered for refined, economical cruising and dependable daily commuting. Emissions compliance for its production period was met through precise fuel metering and exhaust gas recirculation (EGR), allowing it to meet applicable Japanese and North American standards of the late 1980s.
One documented service concern is premature wear of the balance shaft bearings, which can lead to increased engine vibration and noise. This issue, addressed in Honda Service Bulletin 89-068, is attributed to specific lubrication characteristics under sustained high-RPM operation. The subsequent A20A3/A4 variants incorporated revised bearing materials and oil gallery designs.
Honda
Production years 1986–1989 meet applicable Japanese 1986 Emissions Standards and US EPA Tier 0 regulations for its model year (Honda Emissions Certification Docs).
The Honda A20A2 is a 1,956 cc inline‑four naturally aspirated petrol engine engineered for mid‑size sedans (1986-1989). It combines PGM-FI electronic fuel injection with a 12-valve SOHC layout to deliver smooth, linear power delivery and dependable fuel economy. Designed to meet late-1980s emissions standards, it balances everyday drivability with mechanical simplicity.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,956 cc | |
| Fuel type | Petrol | |
| Configuration | Inline‑4, SOHC, 12‑valve | |
| Aspiration | Naturally Aspirated | |
| Bore × stroke | 81.0 mm × 95.0 mm | |
| Power output | 86 kW (117 PS) @ 5,500 rpm | |
| Torque | 162 Nm @ 4,000 rpm | |
| Fuel system | Honda PGM-FI (Programmed Fuel Injection) | |
| Emissions standard | Japanese 1986 Standards / US EPA Tier 0 | |
| Compression ratio | 9.3:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Chain-driven | |
| Oil type | API SF/SG, SAE 10W-40 | |
| Dry weight | 148 kg |
The SOHC 12-valve design offers smooth, linear power ideal for relaxed cruising but lacks the high-RPM performance of later DOHC engines. Strict adherence to 10,000 km oil change intervals is critical to prevent balance shaft bearing wear, a known issue per Honda SIB 89-068. Using the specified API SF/SG grade oil is essential for protecting the older valvetrain and bearings. The PGM-FI system requires clean electrical grounds and a healthy battery for optimal operation. Pre-1988 models may benefit from the updated balance shaft bearing kit if vibration increases.
Oil Specs: Requires API SF/SG specification (Honda Owner's Manual 1987). Modern equivalents (e.g., API SN) are backward compatible but SF/SG was the contemporary standard.
Emissions: Certification applies to 1986-1989 model years for respective markets (Honda Emissions Certification Docs).
Power Ratings: Measured under SAE net standards. Output is consistent across markets for this variant (Honda Group PT-1987).
Honda Technical Service Manual (TSM): A20A2 Engine
Honda Service Information Bulletins (SIB): 87-045, 89-068
Honda Parts Catalogue (EPC): H-86-CA
SAE International: J1349 Engine Power Certification Standards
The Honda A20A2 was used across Honda's CA platform with longitudinal mounting. This engine received platform-specific adaptations-reinforced engine mounts for the Accord and a different intake manifold for the Vigor-creating minor service part variations. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the front of the cylinder block, just below the exhaust manifold (Honda TSM A20A2). The 8th VIN digit for CA4/CA5 chassis indicates engine displacement ('G' for 2.0L). The A20A2 can be visually identified by its single camshaft cover and the "A20A2" casting on the block near the oil filter. Critical differentiation from the carbureted A20A1: A20A2 has a throttle body and fuel rail. Service parts for balance shafts require verification against production date due to mid-cycle bearing updates (Honda SIB 89-068).
The A20A2's primary documented reliability concern is balance shaft bearing wear, with elevated incidence in high-mileage or poorly maintained examples. Honda service data indicated a notable number of repairs were required after 150,000 km, while owner reports frequently cite vibration as a precursor. Infrequent oil changes and use of incorrect viscosity make bearing failure more likely.
Analysis derived from Honda technical bulletins (1986-1989) and aggregated owner repair data (1990-2000). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about HONDA A20A2.
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