7 Common Problems of the Legendary Subaru EJ22 Engine

If you’ll ask any Subaru lover to list his top-rated Subaru engines based on reliability, the EJ22 is without a doubt on their list. The 90s were a mecca when it comes to engine reliability, not only was Subaru creating some of the best boxer engine ever, other car manufacturers like Mercedes were also at the peak of their engine design game (at least reliability wise).

Doing your own homework is really important when it comes to buying a new or used vehicle. We are saying this from our long experience working on cars. What most people are not doing is they don’t care about the maintenance history of the car they’re buying and how this model or engine has proven itself in the past. Big mistake! That’s why, in this article, we are going to share all the information on the EJ22 engine.

First, we are going to cover the specs of the EJ22 engine and learn more about the Subaru EJ22 engine problems. Then, we will also take a look at what models have this engine. So, without further ado, let’s dive into the article.

Basic Subaru EJ22 Engine Specs

The EJ22 is probably one of the most legendary engines that Subaru ever produced, and it’s this engine that definitely helped Subaru to build its legacy.

This 2.2 boxer engine was introduced in 1990 and was produced until 2001 when it was replaced with somewhat unreliable engines that basically destroyed everything that this engine created.

Still, the legacy is there and the 2.2 is one of the most highly regarded engines ever put in production.

This engine is a naturally aspirated boxer engine with four cylinders. The engine design is the simplest it can get. The block is aluminum with cast iron sleeves.

The engine uses a single overhead camshaft engine (SOHC), which means no excessive complications with solenoids and all that stuff that comes with variable valve timing as in modern engines.

And what is good about this engine is that it is a non-interference engine. This means that even if the belt snaps, the engine will not get damaged in the process. This was reportedly changed with the update in 1998.

Nevertheless, here are the full specs of the EJ22 engine.

  • Configuration: 4-cylinder Boxer
  • Displacement: 2.2L
  • Cylinder Bore: 96.9 mm
  • Stroke: 75 mm
  • Block & Head Material: Aluminum
  • Head Design: SOHC
  • Fuel Injection: Port Injection
  • Compression Ratio: 9.5:1 or 9.7:1
  • Horsepower: 130 – 137 hp
  • Torque: 137 – 145 lb-ft (186 – 197 N-m)

Common Subaru EJ22 Engine Problems

Most common Subaru EJ22 engine problems include:

  • Spark Plug Failure
  • Alternator Failure
  • MAF Sensor Failure
  • Front Main Seal Failure
  • Camshaft Seal Failures
  • Oil Pump Seal Failure
  • Timing Belt Failure

We listed the most common problems with the EJ22 engine. Now let’s move on and learn more about these problems in detail and see how these problems are represented.

This is very important in order for you to understand more about a problem on your Subaru because each of these problems creates certain symptoms. And knowing the circumstances when and how they appear, it will be very easy for you to tell if this engine you are looking at has this issue present. So, let’s dive into the issues.

1. Spark Plug Failure

The most common problem with this engine is the spark plug failure. Spark plugs tend to fail on these engines very often. Why so?

Well, these are old cars, the cars that these engines are installed in are 20+ years old and many of them are not even driven a lot.

So, spark plugs tend to fail when the car sits for a really long time. Also, there is a situation when the engine is not maintained properly.

Many of the owners of these cheap cars do not even care about changing these parts and they are somewhat problematic. That’s why the person who buys this car should replace them immediately.

Luckily, these spark plugs are not that expensive after all. You can replace them for less than $50.

The pain is to remove them, since the engine is a boxer and space can be pretty narrow.

Symptoms associated with this problem are engine misfires, rough engine idle, poor performance, and high fuel consumption.

2. Alternator Failure

Another very common problem on these high-mileage Subaru engines is the alternator failure. So, what is the alternator, and what does it do?

The alternator is the component that generates electricity. This component charges up the battery and delivers enough power, so all the accessories and the engine are able to work properly.

Whenever this alternator fails, there will be some problems with the engine. The car will constantly have an empty battery because the alternator is weak and not charging the battery.

This will make the use of the car pretty frustrating. There will be constant malfunctions of the stereo, dash lights, dome lights, and so on.

The solution in many cases is to rebuild the alternator or replace it with a new unit. This can somewhat be expensive but it is the only way to solve this problem.

3. MAF Sensor Failure

Problems with the MAF sensor were also noted on this engine. So, what is a MAF sensor, and what does it do?

The MAF sensor is the sensor that measures the air that enters the intake. Then this measurement is sent to the PCM and the PCM adjusts the air-to-fuel ratio.

If the MAF sensor does not perform well, there will be a problem where you will face running issues.

There can be lean or rich air to fuel mixture and the engine will perform rather poorly. Sometimes even not performing at all.

So, you want to check the MAF and see if it has some contaminants. If there is a lot of dirt, you need to clean it.

If cleaning does not help, you will have to replace the MAF with a new unit that will work. An original OEM part will do the trick just fine. Chinese ones are not that reliable and can be faulty or fail rather quickly.

4. Front Main Seal Failure

Another common problem with the EJ22 engine is the front main seal leak. The front main seal can fail and cause serious oil leaks.

Each engine has two seals, one at the front of the engine and one at the rear. These are called main seals. These are rubber rings that seal the crankshaft.

On this engine specifically, the front main seal starts to leak and whenever it leaks, you will start to lose oil.

Symptoms of this problem understandably will be the oil leaks at the bottom of the engine and in the driveway, as well as oil leaks on the hood, and the low oil level.

If this problem is not solved on time, your engine will starve from oil and will fail completely. So, replace this seal on time before things become serious.

Now let’s move on to the next Subaru EJ22 engine problems.

5. Camshaft Seal Failures

Another seal that tends to leak oil is the camshaft seal. On this engine, there are two camshafts. One per bank.

So, you will see one on the left side and one on the right side. These seals over time become very hard and can cause problems like oil leaks.

It is recommended that you replace them with new ones whenever you do the timing belt service just for good measure.

Because if you don’t do this service, they can start to leak and you will again have to remove the timing belt in order to get them.

6. Oil Pump Seal Failure

The oil pump seals can also fail and develop leaks. These issues are mentioned a number of times on Subaru boards.

So, whenever you replace the main seal and the cam seals, the oil pump seal is also a good idea to replace in order to bulletproof your EJ22 engine.

As we noted, these are 20+ year-old vehicles that need new expendable components replaced if you want to drive them in the foreseeable future.

7. Timing Belt Failure

Timing belt failures are also common on these engines because many people forgot to change their timing belt.

These belts usually have to be changed every 60,000 miles (ca. 96,561 km), along with the necessary hardware like idler pulleys, and tensioners.

Luckily, engines produced until 1997 are non-interference. This means that even if the belt snaps, it will not cause harm. But still, you don’t want it to snap, since the engine will still stall.

Which Models Have The EJ22 Engine?

  • 1990 – 1999 Subaru Legacy
  • 1995 – 1996 Subaru Outback
  • 1995 – 2001 Subaru Impreza


What Are The Common Subaru EJ22 Engine Problems?

Common problems with this engine include spark plug failures, alternator failures, oil leaks from the front main seal, oil pump, and camshaft seals. But overall, there are no serious problems with this engine. It is practically bulletproof and able to run forever if maintained well.

Is The Subaru EJ22 Engine Reliable?

Yes, this is basically one of the most reliable Subaru engines ever put in production. This engine built the reputation of Subaru as a car brand with its reliability. There can be some leaks here and there but overall, this engine is one of the best engines out there.

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