Which Subaru engines to avoid

Are you looking to buy a Subaru and checking which subaru engines to avoid?

You have just landed on the right place!

Subaru is a renowned company that makes automotive engines.

Over the past years, Subaru engines have had many problems.

Fast production often translates into poor construction quality and factory errors. Some of these problems can be serious and damage a company’s reputation that has to improve for decades.

Few of these engines do not comply with the bill. You need to know first and foremost what you are getting yourself into. Naturally, you do not want to lose a lot of money in your car, which later turns into a loss for you.

Subaru engines to avoid

Here are two Subaru engines you should avoid,

1. Subaru 2.5-L Turbo 4 Cylinder:

Owners of the Subaru are a very reliable team, but it is difficult to stay committed to a product that can injure itself and requires an engine change that costs between $ 8,000 and $ 12,000. According to the plaintiffs, the Subaru used a casting system that weakened the piston ring lands (separating the piston rings).

In contrast, the PCV system caused crankcase oil vapor to enter the explosive chamber. To avoid any problem, do not buy this engine. This condition reduces the fuel/octane mixture and places a heavy load on the pistons, breaking and damaging the engine.

The Impreza WRX and WRX STI drivers said their vehicles suddenly lose power, stop or fail the engine, as its internal parts get too hot and sticky. In addition, there is a second case that oil problems in the bearings and crankshafts cause the same failure of the 2.5-L engine.

Owners of the 2009-14 Subaru Impreza WRX and WRX STI models have filed a class-action lawsuit, claiming that pistons and PCV (positive crankcase ventilation) systems in 2. 5-L efficient charging engines could be hot or inefficient, which requires a great master in repair. From previous years, many users have been facing Subaru engine problems.

Also Read: Ford Edge Years to Avoid (Avoid these models)


The Subaru EJ25 is one of the most commonly used Subaru engines in their vehicles. This engine came in two forms – a naturally aspiring 2.5-liter boxing engine with a double camshaft. However, from its inception, EJ 25 was plagued with problems.

These problems include oil burn, oil shortage, and head gasket problems. These problems are not the result of long distances and trauma but poor engine design and engineering. In addition, it had many quality problems.

Now let us talk about these Subaru engine problems one by one.

Subaru engine problems

Almost all EJ 25 engines face head gasket problems. This problem is more common in early models. The Subaru used low-quality head gasket components.

1. Oil Leakage from the Engine:

One of the most common engine problems Subaru owners have experienced to faulty head gaskets. Challenges passed through a few models for five years. The first group is based on the first EJ25D 2.5-liter boxer engine found mainly in Legacy, Legacy Outback, Forester, and Impreza from 1996 to 1999.

The second group of head gasket problems came with the EJ251, EJ252, and EJ253 2.5 liter box engines. Due to Subaru engine problems, every user is frustrated with using cars built-in with these engines.

These head gaskets are prone to external leaks between the cylinder heads and the engine block causing cooling and oil to flow between the head and the block. In both cases, the problem is based on the type of head gasket used, not the engine itself. Of all the problem vehicles, the head gasket used was a single graphite coated head gasket known to lose its adhesion at about the 100,000-mile mark.

Undressing and peeling off this adhesive resulted in the gasket cap of the head becoming vulnerable. Subaru fixed the issue by extending its powertrain warranty and now uses an uncovered multilayer head gasket.

2. Oil and Coolant in the Chamber:

Oil or a cool substance can also penetrate the burning chamber, and it begins to burn. When the oil burns, you can see the black smoke coming out of the exhaust.

There will be clouds of smoke. If a cool object burns during a fire, instead, there will be white smoke coming out of the car exhaust. This white smoke is a clear sign that it is cool and burning.

3. Excessive Oil Use:

Users have consistently reported excessive oil use in their Subarus. Although there was no official recall from Subaru, a class claim was filed. The lawsuit settled out of court because owners claimed that the 2011 to 2015 models Subaru Forester, Outback, Crosstrek, Impreza, and Legacy used high oil prices among common uses.

Boxer Engine of Subaru:

The EN engine series, utilized in Subaru Kei vehicles and trucks, is an exception (Japanese cars and small trucks). The pistons of a boxing engine move in a straight line.

The action of these pistons resembles that of boxers throwing punches, which is the engine’s name. Because the movements are incompatible, they are incompatible, resulting in a bad balanced and smooth motion.

The other bad thing about this engine is that it has two engine heads. If you need to produce two engine heads in each engine instead of one, it means that this engine will be more expensive to produce compared to a four-engine or straight-six engine.

Also read: Shifter moves but does not change gears (Here is why)

The Drawback of the Subaru Boxer Engine:

There are several benefits to boxing. However, it is also a little worse when talking about flat engines or boxers, as people like to call them. One of the disadvantages of this design is its wide range.

Therefore, to get a wider engine, you need to have a wide bay engine. In addition, the stroke is very short, and the piston rods can often fail.

The stroke on these engines needs to be short to fit a flat punch engine into the engine. The Boxer engine is also the reason for Subaru engine problems. In addition, because these rods are much shorter than conventional four-line engines, they can start to develop some problems and break down.

Their base is too small and cannot hold much stress. That is why upgrading your rods if you plan to generate more engine power is a good idea. The large foot makes the engine difficult to operate, too. Therefore, if you want to change your spark plugs, getting the engine on the side won’t be easy.

It is because the engine is so close; it almost touches the frame’s rails. It can lead to costly repairs, and the engine needs to come out completely to repair something. Therefore, it is not DIY-friendly for a particular repair job.

Why Subaru engines fail?

I was researching for Subaru engine problems and I found this amazing video in which the guy explains why Subaru engines fail and all the mechanics involved in it?

You can either watch the video here or check it on youtube here and leave your comments there.

Frequently Asked Questions (FAQs)

What is the most unreliable Subaru?

Subaru Forester and Subaru Outback are the two most unreliable cars with the most complaints by the users.

Which Subarus have engine problems?

Which Subaru engines have head gasket problems?

Which Subaru model is most reliable?

Is the Subaru 3.6 a good engine?

Is the Subaru 2.5 Boxer engine reliable?

Is the Subaru 2.0 engine reliable?

Are boxer engines reliable?

What is wrong with boxer engines?

What are common problems with Subaru?

How good is the Subaru boxer engine?

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