Which Subaru Engines to Avoid: A Comprehensive Guide

Embark on a journey to uncover which Subaru engines to avoid. This guide delves into the depths of Subaru’s engine lineup, highlighting potential pitfalls and providing valuable insights to empower your car-buying decisions.

Subaru engines have a reputation for reliability, but certain models have encountered obstacles along the way. Let’s navigate through the complexities, identify the engines to steer clear of, and explore alternatives that offer a smoother ride.


Subaru, renowned for its signature boxer engines, has produced a range of powertrains over the years. While many Subaru engines are reliable and long-lasting, there are a few that have faced challenges and should be approached with caution.

If you’re considering a Subaru, you’ll want to avoid certain engines known for oil consumption issues. But before you cross all Subarus off your list, check out this article to see if the automaker has addressed this problem: has subaru fixed the oil consumption problem . Even if the issue has been resolved, it’s still crucial to research specific engine models and years to ensure you make an informed decision.

This article aims to identify Subaru engines that have encountered issues and should be avoided when considering a Subaru vehicle. By understanding the potential problems associated with these engines, buyers can make informed decisions and choose a Subaru with a more reliable powertrain.

EJ25 Engine

The EJ25 engine, a 2.5-liter flat-four, was used in various Subaru models from the early 1990s to the mid-2010s. While the EJ25 was generally reliable, it faced issues with head gasket failures, particularly in turbocharged variants. Head gasket failures can lead to coolant and oil leaks, overheating, and engine damage.

Common Problems with Subaru Engines

Which subaru engines to avoid

Subaru engines are generally reliable, but like any other engine, they can develop problems over time. Some of the most common problems with Subaru engines include:

Oil leaks

Subaru engines are known to develop oil leaks, particularly from the camshaft seals and head gaskets. These leaks can range from minor seepage to major leaks that require engine repair.

Timing belt issues

Subaru engines use a timing belt to synchronize the timing of the valves and pistons. If the timing belt breaks or slips, it can cause catastrophic engine damage. It is important to have the timing belt replaced according to the manufacturer’s recommended maintenance schedule.

If you’re considering a Subaru, it’s wise to be aware of which engines to avoid. While the Forester is generally a reliable choice, some older models may have issues with certain powerplants. To learn more about the Forester’s reliability and performance, check out our in-depth review at is subaru forester a good car . It’s always best to do your research before making a decision, especially when it comes to engines that might cause headaches down the road.

Head gasket failure

If you’re in the market for a Subaru, it’s important to know which engines to avoid. Some models have been known to experience head gasket issues, so it’s best to do your research before making a purchase. By the way, do you know if Subaru has remote start? It’s a great feature to have, especially in cold weather.

Check it out and see if your Subaru is equipped with it. Getting back to our topic, here are a few more tips to keep in mind when shopping for a used Subaru.

Head gasket failure is a common problem with Subaru engines, particularly in older models. A failed head gasket can cause coolant and oil to leak into the combustion chambers, leading to overheating and engine damage.

Valve train noise

Subaru engines can develop valve train noise, particularly at high mileage. This noise is often caused by worn or damaged valve lifters or camshafts.

Exhaust manifold cracking

Exhaust manifold cracking is a common problem with Subaru engines, particularly in turbocharged models. A cracked exhaust manifold can cause exhaust leaks and reduced engine performance.

Specific Engines to Avoid

Subaru has a reputation for producing reliable and durable engines. However, like all car manufacturers, they have had their share of problem engines. Here are some specific Subaru engine models that you should avoid:

EJ255: This 2.5-liter turbocharged engine was used in a variety of Subaru models from 2004 to 2014. It is known for its high-pressure fuel pumps that can fail prematurely, leading to engine damage. Additionally, the piston rings can become worn, causing excessive oil consumption and poor performance.

EJ205: This 2.0-liter turbocharged engine was used in a variety of Subaru models from 1998 to 2005. It is known for its head gasket problems, which can lead to coolant and oil leaks. Additionally, the timing belt can fail prematurely, causing catastrophic engine damage.

FB25: This 2.5-liter naturally aspirated engine was used in a variety of Subaru models from 2011 to 2019. It is known for its excessive oil consumption, which can lead to engine damage. Additionally, the valve springs can break, causing the engine to lose power.


  • Prone to head gasket failure, resulting in coolant and oil leaks.
  • Timing belt failure can occur prematurely, leading to catastrophic engine damage.
  • High-pressure fuel pumps can fail, causing engine damage.
  • Piston rings can become worn, leading to excessive oil consumption and poor performance.

Alternatives to Problematic Engines

Subaru offers a range of alternative engine models that are known for their reliability and performance. These engines are often found in newer Subaru vehicles and provide a more dependable driving experience.

The choice of the most suitable engine depends on individual needs and preferences. Factors to consider include power output, fuel efficiency, and overall driving experience. A table comparing the features and specifications of different engines is provided below for reference.

FB25 Series

  • Advantages:
    • Reliable and durable design
    • Good fuel efficiency
    • Smooth and responsive power delivery
  • Disadvantages:
    • Less powerful than some other Subaru engines
    • May require more frequent maintenance

FA20 Series

  • Advantages:
    • Powerful and efficient
    • Lightweight and compact design
    • Excellent handling and performance
  • Disadvantages:
    • More expensive than other Subaru engines
    • May require specialized maintenance

Maintenance Tips for Subaru Engines

Maintaining Subaru engines properly is crucial for their longevity and performance. Regular servicing can prevent or mitigate potential problems and keep your engine running smoothly.

Proper Oil Maintenance

Regular oil changes are essential. Use high-quality synthetic oil recommended by Subaru and change it according to the manufacturer’s schedule, typically every 6,000 to 8,000 miles. Check oil levels frequently and top up as needed.

Timing Belt Replacement

Timing belts are crucial for synchronizing engine components. Replace them as per the manufacturer’s recommendations, usually around 100,000 miles. Ignoring this can lead to catastrophic engine failure.

Spark Plug Inspection

Inspect spark plugs regularly and replace them when necessary. Worn spark plugs can affect engine performance and fuel efficiency.

Coolant System Maintenance

Flush and replace coolant every 30,000 to 50,000 miles to prevent corrosion and overheating. Check coolant levels regularly and top up as needed.

Air Filter Replacement, Which subaru engines to avoid

A clean air filter ensures adequate airflow to the engine. Replace the air filter every 12,000 to 15,000 miles or as recommended by Subaru.

Last Recap: Which Subaru Engines To Avoid

With this newfound knowledge, you’re equipped to make informed choices when it comes to Subaru engines. Remember, proper maintenance is the key to longevity, so follow our expert tips to keep your Subaru running strong.

Stay tuned for more automotive insights and don’t hesitate to reach out with any questions. Happy driving!

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