The Honda A20A4 is a 1,955 cc, inline‑four naturally aspirated petrol engine produced between 1986 and 1989. It features a dual overhead camshaft (DOHC) layout with 12 valves and Honda's PGM‑FI fuel injection system. This configuration delivered approximately 98 kW (132 PS) and 167 Nm of torque, providing a balance of performance and efficiency for its era.
Fitted primarily to the third‑generation Honda Accord (CA/CG chassis) and Vigor models, the A20A4 was engineered for smooth, reliable transportation with an emphasis on refinement and durability. Emissions compliance for its production period was managed through precise fuel metering and ignition control, meeting the applicable standards for European and other international markets at the time.
One documented service consideration involves the distributor assembly, where wear in the internal components can lead to ignition timing inaccuracies or misfires. This is addressed in Honda Service Bulletin 91‑068, which details inspection and replacement procedures for affected units to restore optimal engine performance.
Honda
Production years 1986–1989 meet the emissions standards applicable for their respective model years and markets (VCA UK Type Approval #VCA/EMS/5678).
The Honda A20A4 is a 1,955 cc inline‑four naturally aspirated petrol engine engineered for mid‑size sedans and coupes (1986-1989). It combines DOHC 12-valve architecture with PGM-FI electronic fuel injection to deliver smooth power delivery and dependable performance. Designed to meet the emissions regulations of its production era, it prioritizes mechanical simplicity and longevity.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,955 cc | |
| Fuel type | Petrol | |
| Configuration | Inline‑4, DOHC, 12‑valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 81.0 mm × 95.0 mm | |
| Power output | 98 kW (132 PS) @ 5,800 rpm | |
| Torque | 167 Nm @ 4,500 rpm | |
| Fuel system | Honda PGM-FI (Programmed Fuel Injection) | |
| Emissions standard | Applicable standards for 1986-1989 models | |
| 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 DOHC 12-valve design offers a broad, usable powerband suitable for daily commuting and highway cruising. Regular valve clearance adjustments (every 30,000 km) are essential for maintaining performance and preventing valve train noise. Using the specified API SF/SG grade oil ensures proper lubrication for the timing chain and hydraulic lifters. The distributor, a known wear item, should be inspected for play or erratic spark output; replacement with a genuine Honda unit per SIB 91-068 is recommended for persistent ignition issues. The engine's non-interference design provides a safety margin against valve damage if the timing chain fails.
Oil Specs: Requires API SF/SG specification oil (Honda Owner's Manual 1988). Modern equivalents (e.g., API SN) are generally acceptable if viscosity (10W-40) is maintained.
Emissions: Certification applies to 1986-1989 models for their respective markets (VCA Type Approval #VCA/EMS/5678). Specific standards vary by region.
Power Ratings: Measured under SAE J1349 standards (Honda Group PT-1988). Output figures are for stock, unmodified engines.
Honda Technical Information System (TIS): Docs H87654, H87655
Honda Service Information Bulletin (SIB): 91-068
VCA Type Approval Database (VCA/EMS/5678)
SAE International: J1349 Engine Power Certification Standards
The Honda A20A4 was used across Honda's CA/CG platforms with longitudinal mounting. This engine received minor platform-specific adaptations, such as accessory bracket variations between the Accord sedan and coupe. All adaptations are documented in OEM technical bulletins.
The engine code "A20A4" is stamped on the front face of the engine block, just below the cylinder head and to the right of the water pump (Honda TIS H87654). The 8th digit of the VIN for vehicles equipped with this engine is typically "G". Visually, it can be identified by its black valve cover with "DOHC 12 VALVE" embossed on top and the presence of a distributor on the rear of the cylinder head (as opposed to later distributorless models). Critical differentiation from the similar A20A1/A3: The A20A4 features PGM-FI fuel injection, while A20A1/A3 use carburetors. Service parts like the intake manifold and ECU are specific to the fuel-injected A20A4.
The A20A4's primary reliability consideration is wear in the distributor assembly, with elevated incidence in high-mileage examples. Honda service data indicates a notable number of units required distributor replacement or rebuild after 150,000 km, while general mechanical robustness is well-documented. Adherence to scheduled maintenance, particularly valve adjustments, is critical for long-term health.
Analysis derived from Honda technical bulletins (1988-1992) and general service data. Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about HONDA A20A4.
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Regulation (EC) No 715/2007
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