From 1989 until 2015, the company produced the 2.0-liter Subaru EJ20 gasoline engine, which was fitted to the company’s most well-known models.

Since the engine was frequently improved, there are a number of variations that differ significantly:
From 1989 to 2011, the company produced the EJ20E, which was installed on the Impreza and Legacy in multiple generations. The motor was available in versions with varying compression ratios for the European and Japanese markets.
The EJ201 was installed on the Impreza, Legacy, and Forester and was manufactured between 1998 and 2005. There were two forcing levels available for this power unit: 125 and 135 horsepower.
From 1998 to 2009, EJ202 was manufactured and installed on Legacy and Forester. A lightweight cylinder block was added to this motor in 2003 as part of a significant upgrade.
Only the second generation Forester and the fourth Legacy were equipped with the EJ203, which was manufactured between 2002 and 2009. An electronic throttle set this unit apart from its predecessors.
The Impreza, Legacy, and Forester were equipped with EJ204, which was manufactured between 1999 and 2015. A proprietary AVCS phase control system was installed in the power unit in the majority of versions.
Additionally, this motor has a number of turbo modifications that are combined into the EJ20T series.
Specifications
| Production years | 1989-2015 |
| Displacement, cc | 1994 |
| Fuel system | injector |
| Power output, hp | 115 (European EJ20E) 125 – 155 (Japanese EJ20E) 125 – 135 (EJ201) 130 – 140 (EJ202) 140 (EJ203) 150 – 190 (EJ204) |
| Torque output, Nm | 165 (European EJ20E) 175 – 195 (Japanese EJ20E) 180 – 185 (EJ201) 180 – 190 (EJ202) 186 (EJ203) 180 – 200 (EJ204) |
| Cylinder block | aluminum H4 |
| Block head | aluminum 16v |
| Cylinder bore, mm | 92 |
| Piston stroke, mm | 75 |
| Compression ratio | 9.5 (European EJ20E) 10 (Japanese EJ20E) 9.7 – 10.1 (EJ201) 10.1 (EJ202) 10 (EJ203) 10-11 (EJ204) |
| Features | SOHC (EJ20E, EJ201, EJ202, EJ203) DOHC (EJ204) |
| Hydraulic lifters | until 1994 (EJ20E) no (EJ201, EJ202, EJ203, EJ204) |
| Timing drive | belt |
| Phase regulator | no (except EJ204) AVCS (EJ204) |
| Turbocharging | no |
| Recommended engine oil | 5W-30 |
| Engine oil capacity, liter | 4.0 |
| Fuel type | petrol |
| Euro standards | EURO 2/3/4 |
| Fuel consumption, L/100 km (for Subaru Legacy 1997) — city — highway — combined |
12.6 7.3 9.2 |
| Engine lifespan, km | ~300 000 |
| Weight, kg | 110 (except EJ204) 120 (EJ204) |
Disadvantages of the EJ20 engine
High oil consumption is the most well-known issue with engines in this family; oil is used not only for waste but also leaks from gaskets and seals; a decrease in the system’s lubrication level frequently causes the liners to rotate;
Additionally, the cooling system is unreliable and these motors fear overheating;
The engine speed frequently floats as a result of electronic throttle malfunctions (for the corresponding modifications);
The fourth cylinder frequently develops a knock after 200,000 kilometers, necessitating an overhaul.
