The Honda ET1 is a 1,335 cc, inline‑four naturally aspirated petrol engine produced between 1981 and 1985. It features a single overhead camshaft (SOHC) with two valves per cylinder, prioritizing simplicity and fuel efficiency for compact sedans. Peak output is 75 PS (55 kW) at 5,500 rpm and 103 Nm of torque, delivering adequate performance for its era.
Fitted primarily to the second — generation Honda Accord (AB) and the Honda Prelude (BA1), the ET1 was engineered for econ…

Production years 1981–1985 meet applicable emissions standards for their model year and market of sale (Honda Emissions Certification Docs).
The Honda ET1 is a 1,335 cc inline‑four naturally aspirated petrol engine engineered for compact sedans and coupes (1981-1985). It combines a simple SOHC 8-valve design with a carbureted fuel system to deliver economical and reliable transportation. Designed to meet contemporary emissions standards, it prioritizes low-cost ownership and ease of maintenance.
| Parameter | Value | Source |
|---|---|---|
Displacement | 1,335 cc | |
Fuel type | Petrol | |
Configuration | Inline‑4, SOHC, 8‑valve | |
Aspiration | Naturally Aspirated | |
Bore × stroke | 74.0 mm × 77.5 mm | |
Power output | 55 kW (75 PS) @ 5,500 rpm | |
Torque | 103 Nm @ 3,500 rpm | |
Fuel system | Carburetor (PGM-CARB) | |
Emissions standard | Meets applicable standards for model year | |
Compression ratio | 9.0:1 | |
Cooling system | Water‑cooled | |
Turbocharger | None | |
Timing system | Timing Belt | |
Oil type | API SF/SG 10W-30 or 10W-40 | |
Dry weight | Not specified in available OEM docs |
The Honda ET1 was used across Honda's AB/BA platforms with transverse mounting. This engine received no major facelift revisions during its production run, ensuring parts interchangeability across all model years. All specifications are documented in OEM technical bulletins.
The ET1's primary maintenance-critical item is its timing belt, with failure resulting in total engine destruction. Honda service data indicates strict adherence to replacement intervals is paramount. As a carbureted engine, it is also susceptible to issues related to fuel system aging, such as clogged jets or worn linkages, which are well-documented in service bulletins.
Analysis derived from Honda technical bulletins (1981-1985) and aggregated owner-reported failure data (1985-2023). 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
Yes, the ET1 is renowned for its simplicity and reliability when properly maintained. Its main critical item is the timing belt; failure to replace it on schedule will destroy the engine. With regular oil changes and adherence to the service schedule, including carburetor maintenance and valve adjustments, these engines can easily exceed 200,000 km.
The most frequent issues are related to the carburetor (clogging, wear) and the need for periodic valve clearance adjustments. The critical concern is timing belt failure. Oil leaks from the distributor shaft seal are also common with age.
The ET1 engine was used in the second-generation Honda Accord (AB chassis) from 1981 to 1985 and the first-generation Honda Prelude (BA1 chassis) from 1983 to 1985.
While not a common tuning candidate, the ET1 can see modest gains from carburetor jetting, exhaust upgrades, and ignition timing adjustments. Significant power increases are limited by its small displacement and two-valve-per-cylinder design. Its primary appeal is its simplicity and reliability.
Fuel economy is good for its era. Expect around 7.0-8.0 L/100km (40-35 mpg UK) in mixed driving for a manual transmission Accord. Highway cruising can see figures as low as 6.0 L/100km (47 mpg UK), depending on driving style.
Yes. The ET1 is an interference engine. If the timing belt breaks or jumps time, the pistons will collide with the open valves, causing severe internal damage that requires a costly rebuild or replacement.
Honda originally recommended API SF/SG grade oil. The viscosity (10W-30 or 10W-40) depends on the climate. Using high-quality mineral or semi-synthetic oil and changing it regularly (every 10,000 km or 6 months) is crucial for engine health.
Comprehensive technical documentation and regulatory references
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Regulation (EC) No 715/2007
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