Because of its tough and dependable cars with AWD drivetrains, Subaru has become a well-known brand among auto lovers. But, like every other automotive manufacturer, Subaru has undergone ups and downs throughout the years. The general dependability of the brand has suffered from a few models, especially when it comes to the engines. Here’s a thorough look at the Subaru engines to avoid and why.
The 2.5-liter turbo 4-cylinder, EJ25 Boxer, or EJ205/EJ207/EJ20G series Subaru engines should all be avoided. These engines are more prone to failure than others, usually because of issues with the oil.
Avoid Subaru Engines
During its history, Subaru has produced more than 50 different types of automobile engines. The Concentration/Compact Boxer, or CB, the engine is the newest model. The new engines are noted for delivering higher torque at lower engine speeds, conserving fuel, and making the car safer. Nevertheless, certain vehicles have had problems with rough idling, noise, media system problems, keyless entry, and frozen windows.
2.5-L Turbo 4-cylinder Subaru
In Subaru’s lineup, the 2.5-liter turbo 4-cylinder engine is often employed, especially in the 2009-2014 Impreza and various STI and WRX variants. Although widely utilized, this engine has several problems that have given many drivers pain. Weakening the contact rings that connect the piston ring to the ground is one of the most frequent problems and may seriously harm the engine.
The PCV (positive crankcase ventilation) valve, which controls how exhaust emissions from the crankcase are directed, is another problem. Valve leakage of crankcase oil vapor into the combustion chamber is a common problem with this engine, leading to a polluted fuel mixture and excess stress on the pistons.
As a result, the engine may overheat and overwork, losing power and possibly stalling the car. The engine’s internal parts may suffer from these problems, overheating or sticking and worsening the situation.
Subaru EJ25
The Forester, Outback, and Impreza models all have the Subaru EJ25 Boxer engine. Dual camshaft and normally aspirated 2.5-liter flat-four versions are available. Nevertheless, there have been reports of oil-related problems with this engine, including head gasket failure, oil combusting, and oil scarcity.
Although these issues often develop due to outside agents after prolonged usage, Subarus experience them due to design defects. The horizontal flat-four Boxer engine features pistons that are flat inside the cylinders. Consequently, the fluids often collect close to the head gaskets instead of draining when the engine is shut off. The acids in these fluids gradually erode the seals, leading to the deterioration of the gaskets and the onset of oil and coolant leaks.
It is important to note that Subaru had to replace the gasket material in this engine with a more trustworthy metal shim gasket since it proved unreliable. The EJ25 flat-four Boxer engine, in earlier models, however, often develops gasket problems after 90,000 to 150,000 miles on the odometer. If ignored, a failing head gasket may seriously harm the engine and need expensive repairs.
Subaru EJ205, EJ207, and EJ20G Engines
As a result of blocked rings, the EJ205, EJ207, and EJ20G engines are infamous for their oil-leaking problems. Subaru advised customers to use premium coolant and gasoline to lessen these concerns. However, the majority of drivers continued to have problems.
These engine intercoolers also struggle to maintain constant cooling during high-load runs, which may worsen oil leakage problems. If ignored, these issues may lead to engine damage or even failure. These engines may last longer with routine maintenance and preventive measures like using high-quality oil and monitoring engine temperatures.
How Much Does a Subaru Engine Rebuild Cost?
Various factors, including the car’s model, the degree of the damage, and the shop where you have the engine rebuilt, might affect how much it costs to repair a Subaru engine. Generally, the price may be between $2,000 and $4,500 or above.
If your Subaru is modern and the damage is small, you may get away with merely replacing the head gaskets and a few additional repairs for roughly $1,500 to $2,500. But, the price may easily exceed $4,000 if the damage is more severe and necessitates a whole engine rebuild.
Best Subaru Engines
Subaru EJ257
The horizontally opposed 4-cylinder architecture of this 2.5L engine, built for the USDM 2004 Impreza WRX STI, gives it a lower center of gravity. The EJ257 engine is a fantastic aftermarket option since it has a bore and stroke measurement of 3.92′′ by 3.11′′ and a maximum power output of 300 BHP @ 6,000 RPM. It is said to sometimes have issues with the pistons, however.
Subaru EZ36D
The Subaru Outback utilized this engine, which is the king of the company’s six-cylinder engines, from 2010 to 2019. The EZ36 flat-six engine differs from its predecessor, the EZ30 flat-six engine, in that it has a bigger diameter and stroke and thinner iron cylinder sleeves to suit the larger bore. The stroke is enhanced in line with the use of asymmetric connecting rods. Also, it is renowned for being more dependable than its forerunner.
Subaru EJ20T WRX STI
The performance-oriented STI and WRX variants of the Impreza are where these flat-four boxer engines are most often encountered. They feature a power output range of 197 HP at 6,000 RPM, 2 M6 bolts per coil, a coil on the plug, and special valve covers with the markings 4CAM 16VALVE. Because of its price, accessibility, and torque, the EJ20T is a fantastic aftermarket option.
Subaru FB20D
This engine debuted in 2010 and is a third-generation flat-four engine family member. It comes in 2.5-liter and 2.0-liter displacement options, and its lighter pistons and connecting rods result in a 28% reduction in friction losses. Direct injection is another feature of the FB20D engine, which results in a notable boost in power and economy.
The Boxer Engine
Subaru stands apart from most other automakers because of its distinctive “boxer” engine, which has a horizontally-opposed engine design. Karl Benz invented the boxer engine in 1896, but Subaru has employed it in their vehicles since 1966.
Having a lower center of gravity than conventional inline or V engines, which may aid in enhancing handling and stability, is one of the benefits of the boxer engine. Also, the layout makes greater use of the available space within the engine, which may improve weight distribution and simplify maintenance. Due to the opposing pistons’ ability to negate each other’s vibrations, the engine has a natural balance and runs more smoothly.
The boxer engine does have certain drawbacks, however. The engine’s design makes it more challenging to build and maintain, which is one of its primary drawbacks. The placement of the cylinders and heads may also make it more difficult to reach certain parts, which might raise the cost of maintenance. In addition, the engine’s design may increase the amount of heat produced, resulting in problems like overheating and premature wear.
Despite these issues, many fans hold the boxer engine in high respect and consider it a distinguishing element of Subaru vehicles. Its distinctive appearance and sound have come to represent the brand, and its advantages in terms of efficiency and handling have made it a well-liked option for drivers who place a high emphasis on performance.
Are Subaru Vehicles Reliable?
Subaru vehicles are renowned for their dependability. The manufacturer is known for creating durable cars that handle challenging driving conditions, rugged terrain, and high mileage. Several Subaru models have been known to endure well over 200,000 miles with regular maintenance.
Subaru’s design and engineering philosophy, which emphasizes toughness and endurance, helps the company maintain its reputation for dependability. This strategy is best shown by Subaru’s Symmetrical All-Wheel Drive system, which offers outstanding grip and stability on various road surfaces and weather situations.
Nonetheless, depending on the model and year, Subaru cars might sometimes have problems like defective head gaskets, oil leaks, and excessive oil consumption, just like any other automobile manufacturer. To identify any possible issues and deal with them via routine maintenance and repairs, it is essential to do precise model and year range research.
In general, Subaru has a solid reputation for producing dependable vehicles. Many Subaru owners are committed to the brand because they believe in the lifespan and toughness of their vehicles.
Conclusion
In conclusion, even though Subaru is renowned for building dependable and durable cars, not all of its engines are equal. Specific versions, such as the 2.5-liter turbo 4-cylinder, EJ25 Boxer, or EJ205/EJ207/EJ20G series engines, have had oil-related troubles, which may result in significant damage and costly repairs. But, a few notable engines still provide excellent power output and dependability, such as the Subaru EJ257, EZ36D, EJ20T WRX STI, and FB20D.