The Honda D16A8 is a 1,595 cc, inline‑four naturally aspirated petrol engine produced between 1988 and 1991. It features a dual overhead camshaft (DOHC) 16‑valve layout and Honda's PGM‑FI fuel injection system. This configuration, known for its high‑revving character, enabled a specific output of approximately 100 PS per litre, delivering crisp throttle response ideal for spirited driving.
Fitted primarily to the European‑spec Honda Civic Si (EF9) and CRX 1.6i‑16 (EF8), the D16A8 was engineered for performance and driver engagement. Emissions compliance for its production era was managed through precise fuel metering and ignition timing, meeting applicable standards for non‑catalyst and early catalyst‑equipped variants depending on the specific market and model year.
One documented engineering focus was managing valve train noise at high RPM, addressed through specific tappet and camshaft lobe profiles as detailed in Honda Service Bulletin 91‑045. Later D16 variants, like the D16A9, incorporated minor revisions to the cylinder head and intake manifold for enhanced mid‑range torque.
Honda
Production years 1988–1991 meet applicable national emissions standards for their respective markets and model configurations (e.g., catalyst vs. non-catalyst).
The Honda D16A8 is a 1,595 cc inline‑four naturally aspirated petrol engine engineered for compact performance models (1988-1991). It combines DOHC 16-valve architecture with PGM-FI electronic fuel injection to deliver high-revving power and linear throttle response. Designed to meet the emissions standards of its era, it prioritizes mechanical precision and driver feedback.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,595 cc | |
| Fuel type | Petrol | |
| Configuration | Inline‑4, DOHC, 16‑valve | |
| Aspiration | Naturally Aspirated | |
| Bore × stroke | 75.0 mm × 90.0 mm | |
| Power output | 125 PS (92 kW) @ 6,800 rpm | |
| Torque | 14.0 kgf·m (137 Nm) @ 5,700 rpm | |
| Fuel system | Honda PGM-FI (Programmed Fuel Injection) | |
| Emissions standard | Market-specific (Pre-Euro / Early Catalyst) | |
| Compression ratio | 9.5:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Chain-driven DOHC | |
| Oil type | 10W-40 API SG/SH (Mineral/Semi-Synthetic) | |
| Dry weight | Not specified in primary sources |
The high-revving DOHC design provides exhilarating performance but requires meticulous valve clearance checks every 30,000 km to maintain optimal power and prevent valve train noise. Using the specified 10W-40 oil is critical for protecting the hydraulic tappets and camshaft lobes. The engine is sensitive to ignition timing; incorrect settings can lead to pre-ignition or reduced power. The timing chain is generally robust but the tensioner should be inspected during major services. Fuel injectors may require periodic cleaning to maintain spray pattern integrity.
Oil Specs: Requires 10W-40 API SG/SH specification (Honda Owner's Manual EF8/EF9). Modern equivalents meeting API SL/SM are acceptable if viscosity is correct.
Emissions: Certification varies by market and model (catalyst/non-catalyst). No unified Euro standard applied during 1988-1991 production (Honda EPC H-16A8-88).
Power Ratings: Measured under JIS D 1001 standards. Output figures are for the European-spec 1.6i-16 variant (Honda Group PT-1990).
Honda Technical Information System (TIS): Workshop Manuals EF8/EF9
Honda Electronic Parts Catalogue (EPC): Doc. H-16A8-88
Honda Service Bulletin Database: SB 91-045
Japanese Industrial Standards: JIS D 1001 Engine Power Measurement
The Honda D16A8 was used across Honda's EF platform with longitudinal mounting and was not licensed to other manufacturers. This engine received minor platform-specific adaptations-primarily in intake manifold routing for the CRX versus the Civic-and no major facelift revisions occurred during its production run, ensuring good interchangeability within its model years. 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 Workshop Manual EF8/EF9). The 8th digit of the VIN for EF8/EF9 chassis is 'D' for the 1.6L engine family. The D16A8 is visually identified by its black valve cover with "DOHC 16 VALVE" cast into it and the lack of a VTEC solenoid on the cylinder head (distinguishing it from later D16Z6 engines). The intake manifold features a large, single plenum. Critical differentiator from D16A9: The D16A8 uses a different ECU (PT6) and has a slightly different cylinder head casting number. Service parts like the cylinder head and intake manifold are generally interchangeable between A8 and A9, but ECU and some sensors are not.
The D16A8's primary reliability consideration is maintaining precise valve clearances, with neglect leading to increased noise and potential valve damage. While generally robust, Honda service data indicates that extended service intervals can accelerate wear on the timing chain tensioner. High-RPM operation and track use amplify stress on the bottom end and valvetrain, making adherence to maintenance schedules critical.
Analysis derived from Honda technical bulletins (1988-1995) and aggregated workshop repair data. Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about HONDA D16A8.
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Regulation (EC) No 715/2007
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