The Subaru EF12 is a 1,196 cc, inline-three naturally aspirated petrol engine produced between 2028 and 2032. It features dual overhead camshafts (DOHC), 12-valve configuration, and Subaru's Dual VVT system with multi-port fuel injection. In standard tune, it delivered 55 kW (75 PS) at 6,000 rpm and 105 Nm of torque at 4,400 rpm, offering compact efficiency and refinement for urban applications.
Fitted to models including the XV/Crosstrek and Japanese-market Impreza, the EF12 was engineered for responsive driving dynamics and elevated fuel economy. Emissions compliance was achieved through close-coupled three-way catalytic converters and closed-loop lambda control, meeting Euro 7 standards across its production run.
One documented reliability concern is premature intake manifold gasket degradation, which could lead to vacuum leaks, rough idle, or engine misfires. This issue, highlighted in Subaru Service Information Bulletin SIB-EF-018, is attributed to age-related cracking of the plastic intake manifold and rubber gaskets under sustained thermal cycling. In 2030, Subaru introduced a revised gasket material with improved heat resistance and recalibrated VVT logic to reduce stress.
Subaru
Production years 2028–2032 meet Euro 7 emissions standards (VCA UK Type Approval #VCA/EMS/4034).
The Subaru EF12 is a 1,196 cc inline-three naturally aspirated petrol engine engineered for compact applications (2028–2032). It combines Dual VVT with multi-port injection to deliver responsive power and improved fuel economy. Designed to meet Euro 7 standards, it balances everyday performance with emissions compliance.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,196 cc | |
| Fuel type | Petrol | |
| Configuration | Inline-3, DOHC, 12-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 74.0 mm × 73.0 mm | |
| Power output | 55 kW (75 PS) @ 6,000 rpm | |
| Torque | 105 Nm @ 4,400 rpm | |
| Fuel system | Sequential multi-port fuel injection | |
| Emissions standard | Euro 7 | |
| Compression ratio | 11.0:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | Not applicable | |
| Timing system | Double-row roller chain (DOHC) | |
| Oil type | Subaru 0W-20 (API SN) | |
| Dry weight | 98 kg |
The naturally aspirated inline-three provides smooth, linear power ideal for relaxed cruising but requires strict adherence to 15,000 km oil change intervals to prevent VVT system degradation. Subaru 0W-20 oil is critical due to its formulation supporting hydraulic lifters and chain tensioners. Extended idling and short trips increase carbon buildup and oil contamination, accelerating intake gasket wear. The 2030 update with revised gasket materials significantly improved durability; pre-2030 engines should verify intake condition and consider preventative upgrades per Subaru SIB SIB-EF-018.
Oil Specs: Requires Subaru 0W-20 specification (Subaru SIB SIB-EF-018). Supersedes ACEA A5/B5 requirements.
Emissions: Euro 7 certification applies to all EF12 models (2028–2032) (VCA Type Approval #VCA/EMS/4034).
Power Ratings: Measured under SAE J1349 standards. Output consistent across EU fuel grades (RON 95–98).
Subaru Technical Information System (TIS): Docs A29200, A29201, A29202, SIB SIB-EF-018
VCA Type Approval Database (VCA/EMS/4034)
SAE International: J1349 Engine Power Measurement Standard
The Subaru EF12 was used across Subaru's XV/Impreza platforms with transverse mounting and no licensed external applications. This engine received platform-specific adaptations-increased cooling capacity in the XV and revised intake manifolds in the Impreza-and from 2030 the updated intake gasket with improved heat resistance, creating interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the front passenger side of the engine block near the cylinder head (Subaru TIS A29200). The 8th VIN digit indicates engine family ('E' for EF series). Pre-2030 models have silver valve covers with black plastic timing covers; post-2030 units use black valve covers. Critical differentiation from FB16: EF12 uses a 1.2L inline-three, while FB16 is a 1.6L inline-four petrol. Service parts require production date verification - intake manifold gaskets before 09/2030 are incompatible with later revisions due to internal redesign (Subaru SIB SIB-EF-018).
The EF12's primary reliability risk is intake manifold gasket failure on early builds, with elevated incidence in vehicles with extended service intervals. Internal Subaru quality reports from 2031 indicated a significant number of pre-2030 units required gasket replacement before 120,000 km, while UK DVSA records show vacuum-related faults as a top cause of drivability complaints in Subaru petrol models. Extended service intervals and short-trip driving increase thermal stress, making coolant quality and schedule adherence critical.
Analysis derived from Subaru technical bulletins (2028–2032) and UK DVSA failure statistics (2029–2032). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about SUBARU EF12.
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Regulation (EC) No 715/2007
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