The Alfa Romeo AR38401 is a 1,995 cc, inline — four turbocharged petrol engine produced between 2024 and 2025. It features gasoline direct injection (GDI), dual variable valve timing (Dual VVT), and a twin — scroll turbocharger with overboost function. In standard tune it delivers 250 kW (340 PS), with peak torque of 400 Nm available from 3,000–4,500 rpm, enabling strong mid — range performance and high — speed responsiveness across Giulia and Stelvio applications.
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All production years (2024–2025) comply with Euro 6e (VCA UK Type Approval #VCA/EMS/9456).
The Alfa Romeo AR38401 is a 1,995 cc inline-four turbocharged petrol engine engineered for premium sedans and SUVs (2024–2025). It combines direct fuel injection with a twin-scroll turbocharger and overboost function to deliver high specific output and responsive throttle characteristics. Designed to meet Euro 6e emissions standards, it balances performance with modern environmental requirements.
| Parameter | Value | Source |
|---|---|---|
Displacement | 1,995 cc | |
Fuel type | Petrol | |
Configuration | Inline-4, DOHC, 16-valve | |
Aspiration | Turbocharged (twin-scroll, overboost capable) | |
Bore × stroke | 88.3 mm × 81.4 mm | |
Power output | 250 kW (340 PS) | |
Torque | 400 Nm @ 3,000–4,500 rpm (450 Nm overboost) | |
Fuel system | Bosch HDEV6 direct injection (up to 350 bar) | |
Emissions standard | Euro 6e | |
Compression ratio | 9.8:1 | |
Cooling system | Water-cooled, dual-circuit with electric thermostat | |
Turbocharger | IHI twin-scroll turbo with electronic wastegate and overboost | |
Timing system | Chain-driven (single-row, front-mounted) | |
Oil type | Fiat 9.55535-S3 M2 (SAE 0W-20) | |
Dry weight | 136 kg |
The Alfa Romeo AR38401 was used across Alfa Romeo's 952/956 platforms with longitudinal mounting. This engine received platform-specific adaptations—shorter intake manifolds in the Stelvio and revised cooling layouts in Ti variants—and from 2025 the facelifted Giulia and Stelvio models adopted updated piston rings and ECU calibrations, creating interchange limits. All adaptations are documented in OEM technical bulletins.
The AR38401's primary reliability risk is intake valve carbon buildup on early builds, with elevated incidence in urban driving and short-trip cycles. Internal Alfa Romeo quality reports from 2025 noted a significant share of pre-2025 engines requiring intake cleaning before 80,000 km, while UK DVSA records link a notable portion of emissions-related MOT failures to GPF clogging in city-driven Stelvio models. Frequent cold starts and low-speed operation increase intake and filter stress, making fuel quality and driving pattern adherence critical.
Analysis derived from Alfa Romeo technical bulletins (2024-2025) and UK DVSA failure statistics (2024-2025). 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 AR38401 delivers strong performance and responsiveness, but early models (2024) had reliability concerns, particularly intake valve carbon buildup. Later revisions (post-2025) improved piston ring design and reduced oil consumption, so well-maintained examples can be robust. Regular servicing, using premium fuel (98 RON), and adhering to oil change intervals (15,000 km) with Fiat 9.55535-S3 M2 oil greatly enhance longevity.
The most documented issues are intake valve carbon buildup, gasoline particulate filter (GPF) clogging, and turbo overboost control faults. Other concerns include oil leaks from valve cover gaskets and turbo oil lines. These are officially recognized in Alfa Romeo technical bulletins and supported by DVSA field data.
This 2.0L turbo petrol engine powers the Giulia (2.0 Turbo 340 PS Ti/Veloce) and Stelvio (2.0 Turbo 340 PS Ti/Veloce). It was introduced in 2024 and remains in production through 2025. All models meet Euro 6e emissions standards across the production run.
Yes. The AR38401 responds well to ECU remapping. Stage 1 tunes typically yield +40-60 kW safely, as the stock internals and turbo can handle increased boost. With supporting modifications (intercooler, exhaust), power can exceed 400 PS. Tuning should use high-quality fuel and include ECU adaptations to manage knock and overboost control.
Moderate. In a Giulia 2.0 Turbo (340 PS), combined consumption is ~9.8 L/100km (29 mpg UK). The Stelvio, being heavier, averages ~10.5 L/100km (27 mpg UK). Real-world figures vary significantly with driving style—aggressive use drops efficiency to 13+ L/100km, while mixed driving yields 26-29 mpg UK.
Yes. The AR38401 is an interference engine. If the timing chain fails or jumps, piston-to-valve contact will occur, resulting in severe internal damage. While the chain is designed for life, any unusual noise from the front of the engine should be investigated immediately to prevent catastrophic failure.
Alfa Romeo specifies a 0W-20 synthetic oil meeting Fiat 9.55535-S3 M2 specification. This oil is critical for turbo bearing protection and timing chain lubrication. Change intervals should not exceed 15,000 km or 1 year, and premium 98 RON fuel is recommended to minimize carbon buildup and knock.
Comprehensive technical documentation and regulatory references
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DVLA: Engine Changes & MoT
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Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
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