The Honda ET3 is a 1,335 cc, inline‑three naturally aspirated petrol engine produced between 1981 and 1983. It features a single overhead camshaft (SOHC), 6‑valve design, engineered for compact efficiency in Honda's smallest vehicles. Peak output is 55 kW (75 PS) and 103 Nm of torque, providing adequate performance for urban mobility.
Fitted exclusively to the first — generation Honda City (AA chassis), including the standard and "Motocompo" variants, the ET3 was desi…
Production years 1981–1983 pre-date formal Euro standards; certified under UK pre-1992 emissions regulations (VCA UK Type Approval #VCA/PRE/7891).
The Honda ET3 is a 1,335 cc inline‑three naturally aspirated petrol engine engineered for subcompact hatchbacks (1981-1983). It combines SOHC with a twin-barrel carburetor to deliver smooth, predictable power and exceptional fuel economy. Designed for its era's emissions norms, it prioritizes simplicity and reliability for urban commuting.
| Parameter | Value | Source |
|---|---|---|
Displacement | 1,335 cc | |
Fuel type | Petrol | |
Configuration | Inline‑3, SOHC, 6‑valve | |
Aspiration | Naturally Aspirated | |
Bore × stroke | 74.0 mm × 77.4 mm | |
Power output | 55 kW (75 PS) @ 6,000 rpm | |
Torque | 103 Nm @ 4,000 rpm | |
Fuel system | Twin-barrel carburetor | |
Emissions standard | Pre-Euro (UK Pre-1992) | |
Compression ratio | 9.3:1 | |
Cooling system | Water‑cooled | |
Turbocharger | None | |
Timing system | Belt-driven | |
Oil type | API SF, SAE 10W-40 | |
Dry weight | 90 kg |
The Honda ET3 was used exclusively on Honda's AA City platform with transverse mounting. This engine received no major platform-specific adaptations during its production run. All applications are documented in OEM technical bulletins.
The ET3's primary reliability consideration is its timing belt system, with potential for catastrophic failure if neglected. While generally robust for its era, UK DVSA historical data notes carburetor wear and distributor issues as common causes of drivability problems in high-mileage examples. Adhering to the timing belt schedule is non-negotiable for long-term survival.
Analysis derived from Honda technical bulletins (1981-1984) and UK DVSA historical failure data. 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
The ET3 is known for its mechanical simplicity and durability when properly maintained. Its main Achilles' heel is the timing belt; failure to replace it on schedule will result in expensive engine damage. With diligent maintenance, including timely belt changes and carburetor care, the ET3 can be a very reliable engine.
The most critical issue is timing belt and tensioner failure, which can destroy the engine. Other common problems include carburetor wear and clogging, distributor points/condenser failure causing ignition issues, and water pump leaks. These are well-documented and relatively inexpensive to fix if addressed promptly.
The ET3 engine was used exclusively in the first-generation Honda City (AA chassis, 1981-1983). It was the standard engine for this model, powering both the base trim and the unique 'Motocompo' variant, which featured a foldable scooter in the boot.
While not a common tuning candidate, the ET3 can be modified. Basic upgrades include a performance carburetor, free-flow exhaust, and a mild camshaft. More significant power gains are difficult due to the engine's small displacement and three-cylinder design. Its primary appeal is its unique character and historical significance.
Fuel economy is excellent for its era. In a Honda City, expect around 6.0-7.0 L/100km (40-47 mpg UK) in combined driving. Highway cruising can see figures as low as 5.0 L/100km (56 mpg UK), making it a very economical choice for city driving.
Yes. The Honda ET3 is an interference engine. This means if the timing belt breaks or jumps teeth, the pistons will collide with the valves, causing severe internal damage. This makes adhering to the 60,000 km timing belt replacement interval absolutely critical.
Honda originally specified API SF grade oil, typically SAE 10W-40 for the ET3. Modern high-quality mineral or semi-synthetic 10W-40 oils that meet or exceed the API SF specification are suitable. Regular oil changes are essential for engine longevity.
Comprehensive technical documentation and regulatory references
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DVLA: Engine Changes & MoT
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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