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Jun 1, 2019 - 6 minute read

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Subaru Engine Codes Explained

Subaru Engine Codes Explained
(Last Updated On: March 6, 2020)

Subaru is one of the Fuji Heavy Industries automobile manufacturing divisions in Japan. It is the second largest automobile production units in the world. Many people know Subaru well because of its all-wheel drive-train layouts and boxer engine layout which are mostly used in cars above 1500 cc.

Subaru Engine Codes Meanings

Subaru engine codes differ as they include four or five character code used for identification purposes:

E: E is the first letter that stands for the engine

Second Letter: engine family is the second letter.  For example, in the image below, the family is J:

Check engine code subaru

Check engine code subaru

Third and Fourth Digits: The next two digits represent the displacement of the engine. The displacement of the engine in the image to the above is 25.

Last Optional Character: The last optional character which happens to be fifth is an identifier that marks revisions. The revisions, in this case, may include turbo, Fuel Injection, DOHC, etc.

1. The Subaru EK Subaru Engine Codes

The first engine code is Subaru EK engine with two cylinders. It was mostly used between 1958 up to 1989. However, the series had a two-stroke cycle. The following are examples of two strokes Subaru EK series.

Subaru engine codes ej

Subaru engine codes ej

1. There is air cooled which consists of:

EK31 series with the following codes:

EK31 It’s used in Sambar and Subaru 360. Subaru 360 was used in 1958-1968 while Sambar was used in 1961-1970.

EK51 was found in Japan and North America where it was used in the Subaru 450 (MAIA).

EK32 was used in the 360 Young SS and Subaru 360 in 1968-70.

EK33 was used in the Subaru Sambar, 1970–1973 and Subaru R-2, 1969–1971.

2. There is also water cooled which consists of:

EK34 code used in the Subaru R-2 1971 Oct, -1972 July, Subaru Sambar 1973 Feb-1976 Feb and Subaru Rex 1972.07-1973.10.

3. There are also EK Four-strokes that include:

They are water cooled and include:

EK21 which is used in the Subaru Sambar Feb 1976-May 1976 and Subaru Rex K22 from 1973 Oct–1976 May.

EK22 is used in the Subaru Sambar 5 from 1976.05 until 1977.03 and Subaru Rex 1976.05–1977.05.

EK23 used in the Subaru Sambar 1977–1990 and Subaru Rex from 1977.05–1989.

EK23ThreeValve used in the Subaru Sambar 1989–1990 Subaru Rex Viki from 1986 to 1989.

EK23 ThreeValve Supercharger used in the Subaru Rex Supercharger (1988–1989). EK23 Turbo used in the Subaru Rex Combi (1983–1986).

EK42 used in the Sambar/700 and Subaru Rex. EK23 ThreeValve Turbo used in the Subaru Rex VX (1986–1989).

2. The Subaru EF Subaru Engine Codes

The other Subaru engine is Subaru EF. It is has three-cylinder, liquid cooled, and four strokes.

The engine is also fitted with SOHC. It appeared at the time when ENO5 was replacing EK.

Subaru Engine Identification

Subaru Engine Identification

Subaru EF engine codes are as follows: EF10 and EF12 all fitted with two valves per cylinder. They are all used by Subaru Justy.

3. The Subaru EA Subaru Engine Codes

The third Subaru engine is a Subaru EA engine. It is a four-cylinder engine which also believed to be liquid-cooled.

However, it is also parallel opposed to boxer four-strokes. The engine was used up to 1994 in most models. They include EA52, EA61, EA62, EA63, EA71, EA81, EA81T, EA82, and EA82T.

4. The Subaru EE Subaru Engine Codes

The fourth Subaru engine is the Subaru EE engine. It also introduced the first boxer with engine consuming diesel in 2007 at the Geneva auto show in a passenger car.

Subaru EE Subaru Engine Codes

Subaru EE Subaru Engine Codes

The engine is 2.0L DOHC designated the EEE20. The engine has 1998 cc total displacement from a square 86 mm multiply by 86 mm.

The engine also uses five main bearings. Denso is the one that manufactures the common rail solenoid injector. The injector operates at 180 MPa (26,000 psi).

EE20 was the code of the engine Fuji Heavy Industries (FHI) had like three years until it concluded the marquee that needed a diesel engine to compete in Europe.

EE20 was sold to the European market where it was fitted to Legacy (sedan and wagon) and Outback cars. After slight modification, it was also used in Impreza and Forester models.

5. The Subaru EJ Subaru Engine Codes

The fifth one is the Subaru EJ engine and was introduced back in 1989. It was used in legacy vehicles at that moment.  Subaru EJ was launched to replace the EA engines.

The engine was made from scratch with four valves per cylinder and five main crankshaft bearings. The engine can be either one timing belt or DOHC or SOHC.  However, it is right to note that the fifth digit that describes whether it’s the engine without even seeing.

Subaru engine code

Subaru engine code

They include the following codes: EJ15, EJ16, EJ18, EJ20, EJ22, EJ25, and EJ30. The EJ15 was used in the Subaru Impreza in 1990-2003. Subaru Impreza used the EJ16 in 1993-2006. The EJ18 was used by JDM Subaru legacy and Subaru Impreza and Euro in 1993-1996.

EJ20 is available in Europe, Australia, and Japan and used on most models.  The EJ22 was used in Subaru Legacy and Subaru Impreza in 1989-2001.

However, the EJ25 code is used in most models of Subaru from 1995 to present. The EJ30 is believed to one of the unique limited engines Subaru may ever have.

6. The Subaru EL Subaru Engine Codes

The sixth engine is Subaru EL engine and has codes that show its type. Subaru EL is the one that replaced the EJ15.

The JDM Subaru Impreza 1.5R uses EL engine. Since the model produced in 2006, the engine is in use.

The engine shares many components with engine EJ like the EJ25 crankshaft. The engine also has DOHC cylinder heads.

7. The Subaru EN Subaru Engine Codes

The seventh Subaru engine code is found on Subaru EN engine. The Subaru EN inline-four engine replaced the straight-two EK series engine in 1988.

The straight-two engine was initially was well known as an air-cooled engine; hence, there was a need for a modification to be a water-cooled engine.

Currently, all Kei trucks and Kei cars use EN engine produced by Subaru.


As you can see, there are many Subaru engine codes. Subaru is not relenting, producing more powerful engines with unique codes. It is committed to ensuring that it gives its customers the best of the best. Subaru engine codes play a significant role in defining the type of engine a vehicle can replace or use. Lastly, it is essential for the automakers to know every code of the engine and where to be fitted.