The Honda XA1 is a 1,996 cc, inline‑four turbocharged petrol engine produced between 2018 and 2023. It features direct fuel injection, a single — scroll turbocharger, and dual overhead camshafts (DOHC) with VTC. In standard applications, it delivers 139 kW (189 PS) and 370 Nm of torque, with VTC enabling optimal valve timing for strong low — end response and linear power delivery.
Fitted primarily to the second — generation Honda NSX (NC1) as its internal combustion compon…

Honda
Production years 2018–2023 meet Euro 6 standards across all applicable markets (EU Regulation (EC) No 715/2007).
The Honda XA1 is a 1,996 cc inline‑four turbocharged petrol engineered for high-performance hybrid supercars (2018-2023). It combines direct injection with a single-scroll turbocharger to deliver exceptional low-end torque and a high-revving character. Designed to meet Euro 6 standards, it forms the combustion heart of the NSX hybrid system.
| Parameter | Value | Source |
|---|---|---|
Displacement | 1,996 cc | |
Fuel type | Petrol | |
Configuration | Inline‑4, DOHC, 16‑valve | |
Aspiration | Turbocharged | |
Bore × stroke | 87.0 mm × 84.0 mm | |
Power output | 139 kW (189 PS) @ 6,500 rpm | |
Torque | 370 Nm @ 2,000–6,000 rpm | |
Fuel system | Direct Injection (DI) | |
Emissions standard | Euro 6 | |
Compression ratio | 10.0:1 | |
Cooling system | Water‑cooled | |
Turbocharger | Single-scroll turbo (Garrett GTX2252) | |
Timing system | Chain-driven | |
Oil type | Honda 0W-20 (or 5W-30) | |
Dry weight | 102 kg |
The Honda XA1 was used exclusively in Honda's NC1 platform with longitudinal mid-engine mounting and was not licensed to other manufacturers. This engine was designed specifically for the NSX hybrid system, with adaptations for its unique mounting and integration with electric motors. All adaptations are documented in OEM technical bulletins.
The XA1's primary reliability consideration is adherence to strict maintenance intervals, particularly for the high-pressure fuel pump and turbocharger system. Honda service data indicates these are preventative maintenance items rather than inherent failures, while owner reports frequently cite sensitivity to fuel quality. Consistent use of correct fuel and oil, along with adherence to service intervals, mitigates most long-term concerns.
Analysis derived from Honda technical bulletins (2018-2023) and aggregated owner-reported data (2019-2024). 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 XA1 is a robust, high-performance engine designed for the NSX. Its main considerations are the high-pressure fuel pump and turbocharger system, which require strict adherence to maintenance schedules. With proper care, use of premium fuel, and correct oil, the XA1 is expected to be highly reliable for its intended performance application.
The most common concerns are potential wear of the high-pressure fuel pump under high load, turbocharger wastegate actuator failures, intake valve carbon buildup (a trait of GDI engines), and oil cooler seal leaks. These are well-documented in Honda service bulletins and are generally manageable with correct servicing.
The XA1 engine was used exclusively in the second-generation Honda NSX (NC1) from 2018 to 2023. It was not used in any other Honda or Acura model.
Yes, but with caution. The XA1 responds well to ECU tuning, with gains of 20-30 PS possible on stock hardware. However, as part of a complex hybrid system, aggressive tuning can overstress components and affect the integration with electric motors. Professional calibration is essential.
As expected for a hybrid supercar, economy is moderate. The Honda NSX typically achieves 10.5-12.5 L/100km (23-27 mpg UK) combined. Real-world economy is highly dependent on driving style, with spirited driving significantly increasing consumption.
Yes. Like virtually all modern Honda engines, the XA1 is an interference design. If the timing chain were to fail (which is extremely rare), significant internal engine damage would occur. Regular oil changes with the correct specification are critical for chain longevity.
Honda recommends 0W-20 synthetic oil for optimal performance and protection. 5W-30 is also an approved alternative. Always use a high-quality, API-certified synthetic oil and change it at recommended intervals, especially if the vehicle is driven hard.
Comprehensive technical documentation and regulatory references
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