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 designed for nimble, economical city driving. Emissions compliance for its production period was met through a twin-barrel carburetor and basic exhaust systems, aligning with pre-Euro standards common for its era.
One documented service concern is premature wear of the timing belt tensioner bearing, potentially leading to belt slippage or failure. This issue, addressed in Honda Service Bulletin 82-008, is often linked to inadequate lubrication or contamination, necessitating early replacement to prevent engine damage.
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 inline-three layout offers a compact, lightweight package ideal for small cars but can exhibit inherent vibration at certain RPMs. The timing belt requires replacement every 60,000 km to prevent failure, which can cause valve damage as it is an interference design. Using the specified 10W-40 oil and adhering to 5,000 km service intervals is critical for longevity. The carburetor may require periodic adjustment or cleaning for optimal performance, as per Honda TIS procedure H-FI-002.
Oil Specs: Requires API SF specification, SAE 10W-40 viscosity (Honda Owner's Manual, 1982 City).
Emissions: Pre-dates formal Euro standards; certified under UK pre-1992 regulations (VCA Type Approval #VCA/PRE/7891).
Power Ratings: Measured under SAE J1349 standards. Output is consistent across model years (Honda TIS Doc. H-ENG-006).
Honda Technical Information System (TIS): Docs H-ENG-006, H-FI-002, SB 82-008
VCA Type Approval Database (VCA/PRE/7891)
SAE International: J1349 Engine Power Certification Standards
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.
Locate the engine code stamped on the front of the engine block, near the timing belt cover (Honda TIS H-ENG-ID). The 8th digit of the VIN for ET3-equipped Cities is typically 'B'. Visually, the engine is easily identified by its unique inline-three cylinder layout and the twin-barrel carburetor on the intake side. Critical differentiation from the E0 engine: The ET3 has a larger displacement (1,335 cc vs. 1,169 cc) and a distinct bore/stroke ratio. Service parts like the cylinder head and block are unique to the ET3.
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.
Find answers to most commonly asked questions about HONDA ET3.
Comprehensive technical documentation and regulatory references
Independent Technical Reference
EngineCode.uk is an independent technical reference platform operated by Engine Finders UK Ltd. We are not affiliated with HONDA or any other manufacturer. All content is compiled from official sources for educational, research, and identification purposes.
Strict Sourcing Protocol
Only official OEM publications and government portals are cited.
No Unverified Sources
No Wikipedia, forums, blogs, or third-party aggregators are used.
Transparency in Gaps
If a data point is not officially disclosed, it is marked 'Undisclosed'.
Regulatory Stability
EU regulations are referenced using CELEX identifiers for long-term stability.
HONDA Official Site
Owner literature, service manuals, technical releases, and plant documentation.
EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
GOV.UK: Vehicle Approval & V5C
UK vehicle approval processes, import rules, and MoT guidance.
DVLA: Engine Changes & MoT
Official guidance on engine swaps and inspection implications.
Vehicle Certification Agency (VCA)
UK type-approval authority for automotive products.
Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
WLTP and RDE testing procedures for emissions certification.
GOV.UK: Vehicle Approval
UK compliance and certification requirements for imported and modified vehicles.
VCA Certification Portal
Type-approval guidance and documentation.
Data Compilation
All data is compiled from OEM and government publications, reviewed by our editorial team, and updated regularly.
Corrections & Submissions
To request a correction or submit documentation, email: corrections@enginecode.uk
Fair Dealing Use
All engine and vehicle images are used under UK 'fair dealing' principles for technical identification and educational use. Rights remain with their respective owners.
Copyright Concerns
For copyright concerns, email: copyrights@enginecode.uk
GDPR Compliance
EngineCode.uk complies with UK GDPR. We do not collect personal data unless explicitly provided.
Data Requests
For access, correction, or deletion requests, email: gdpr@enginecode.uk
Trademark Notice
All trademarks, logos, and engine codes are the property of their respective owners. Use on this site is strictly for reference and identification.
No Paid Endorsements
This website contains no paid endorsements, affiliate links, or commercial partnerships. We do not sell parts or services.
Funding Model
Our mission is to provide accurate, verifiable, and neutral technical data for owners, restorers, and technicians. This site is self-funded.
All specifications and compatibility data verified against officialHONDA documentation and EU/UK regulatory texts. Where official data is unavailable, entries are marked “Undisclosed“ .
All external links open in new tabs. Please verify current availability of resources.
