6 Subaru 2.4 Turbo Engine Problems & How to Fix Them

Short answer: The most frequent issues reported with the Subaru 2.4L turbo engine include carbon buildup on intake valves, weak phasers, oil consumption issues, and software glitches. These problems can arise from the engine’s design, the materials used, and the high-performance nature of turbocharged engines.

Despite its strong reputation, some Subaru 2.4L turbo engine owners face problems that can affect the vehicle’s performance.

Recognizing these common issues and understanding how to address them can help you avoid expensive repairs and reduce downtime.

In this article, we’ll discuss six common problems with the Subaru 2.4L turbo engine and how to fix them.

Problem #1 Carbon Buildup on Intake Valves

• What it is: Direct injection engines, like the Subaru 2.4L turbo, are prone to carbon buildup on the intake valves. This can lead to rough idling, reduced fuel efficiency, and even engine misfires.
• Potential causes: The fuel injectors spray fuel directly into the combustion chamber, bypassing the intake valves. This means that the detergents in the fuel, which usually clean the valves, don’t reach them, leading to carbon deposits.
• Symptoms: Rough idling; Reduced fuel efficiency; Engine misfires; Loss of power; Check engine light
• Potential fix: Regularly using a fuel system cleaner can help mitigate this issue. For severe cases, a professional walnut blasting service can clean the intake valves effectively. Additionally, following a strict maintenance schedule and using high-quality fuel can help reduce the risk of carbon buildup.

Problem #2 Weak Phasers

• What it is: Some Subaru 2.4L turbo engines have been reported to have weak phasers, which can cause a rattling noise during startup and affect the engine’s timing.
• Potential causes: The phasers, which adjust the camshaft timing, can wear out prematurely due to the high stresses of turbocharged operation.
• Symptoms: Rattling noise during startup; Inconsistent engine timing; Reduced engine performance; Check engine light
• Potential fix: Replacing the phasers with updated, more robust versions can resolve this issue. Subaru has issued service bulletins addressing this problem, so it might be covered under warranty. Regular maintenance and timely inspections can help identify and address this issue early.

Problem #3 Oil Consumption Issues

• What it is: Excessive oil consumption is another common issue with the Subaru 2.4L turbo engine. This can lead to low oil levels and potential engine damage if not monitored closely.
• Potential causes: High-performance turbocharged engines can consume more oil due to the increased pressure and heat. Additionally, piston ring design and valve guide seals can contribute to this problem.
• Symptoms: Low oil levels; Frequent need to top off oil; Blue smoke from the exhaust; Engine knocking or unusual noises; Reduced engine performance
• Potential fix: Regularly checking and topping off the oil level is crucial. If the consumption is excessive, Subaru dealers can perform an oil consumption test to determine if repairs are needed, which might include replacing piston rings or valve guide seals. Using high-quality oil and following the manufacturer’s maintenance schedule can also help manage oil consumption.

Problem #4 Software Glitches

• What it is: Some owners have reported software-related issues that can cause the engine to run rough or trigger the check engine light.
• Potential causes: The engine control unit (ECU) software may have bugs or require updates to optimize performance and address known issues.
• Symptoms: Engine running rough; Check engine light turning on; Inconsistent engine performance; Poor fuel efficiency
• Potential fix: Subaru often releases software updates to address these problems. Visiting a dealer to have the ECU reprogrammed with the latest software can resolve these issues. Additionally, keeping up with regular maintenance and checking for any available software updates can help prevent these glitches.

Problem #5 Turbocharger Failure

• What it is: Turbocharger failure can occur, leading to a loss of power and increased exhaust smoke.
• Potential causes: The turbocharger operates under extreme conditions, and issues like oil starvation, bearing wear, or foreign object damage can lead to failure.
• Symptoms: Loss of engine power; Increased exhaust smoke; Unusual noises from the turbocharger; Check engine light; Reduced fuel efficiency
• Potential fix: Regular maintenance, including timely oil changes with high-quality oil, can help prevent turbocharger issues. If the turbocharger fails, it will need to be replaced, which can be a costly repair. Additionally, ensuring the air intake system is clean and free of debris can help protect the turbocharger from foreign object damage.

Problem #6 Cooling System Problems

• What it is: Overheating and coolant leaks are reported issues with the Subaru 2.4L turbo engine.
• Potential causes: The high-performance nature of the engine puts extra stress on the cooling system components, which can lead to leaks or failures.
• Symptoms: Engine overheating; Visible coolant leaks; Low coolant levels; Warning lights on the dashboard; Unusual engine noises; Steam or smoke from the engine bay
• Potential fix: Regularly inspecting the cooling system, including hoses, radiator, and water pump, can help catch issues early. Replacing worn or damaged components and ensuring the coolant is at the proper level and mixture can prevent overheating. Additionally, using high-quality coolant and considering an upgraded radiator or cooling system components can provide extra protection.

Is There a Subaru 2.4 Turbo Engine Recall?

As of now, there isn’t a widespread recall specifically for the Subaru 2.4L turbo engine. However, there have been some reported issues with this engine, such as carbon buildup on intake valves, weak phasers, and software issues.

Subaru has addressed some of these problems through warranty repairs and technical service bulletins (TSB) such as this one.

This TSB, issued by Subaru in July 2021 instructs dealerships to replace both the EGI harness and ECM in vehicles affected by a Subaru voluntary emissions recall for certain 2021 model year vehicles with a 2.4L Turbo engine.

If you’re experiencing issues with your Subaru 2.4L turbo engine, it might be a good idea to contact your local Subaru dealer for the latest information and support.

Who Pays for the Problems I’m Having?

The responsibility for covering the costs of any issues with your Subaru 2.4L turbo engine can depend on several factors.

If your vehicle is still under warranty, Subaru should cover the costs of repairs for any defects or issues that fall under the warranty terms.

Additionally, manufacturers sometimes issue service bulletins for known issues. While these are not recalls, they may cover the cost of repairs if your vehicle is affected.

If you have an extended warranty or service contract, it might also cover the repairs. In some cases, even if your vehicle is out of warranty, the manufacturer or dealer might offer to cover part or all of the repair costs as a goodwill gesture.

It’s best to contact your local Subaru dealer to discuss your specific situation. They can provide detailed information on what might be covered and any steps you need to take.

The Advantages of Consulting with an Attorney

If you’re facing repeat warranty repairs involving your Subaru 2.4L turbo engine, seeking advice from an experienced lemon law attorney is essential for addressing these concerns.

A knowledgeable attorney can offer valuable insights into your consumer rights and determine if your situation meets the criteria for a lemon law claim.

These legal professionals are skilled in negotiating with manufacturers and dealerships, advocating for necessary repairs, a replacement vehicle, or financial compensation to ensure your rights are upheld.

Should legal proceedings be required, your attorney will represent you in court, handling all facets of the litigation process to protect your interests.

The Lemon Law Experts offer exceptional legal assistance for individuals dealing with defective Subaru vehicles, including those with the 2.4L turbo engine.

Since 2009, their attorneys have successfully obtained significant compensation for clients through refunds and settlements with major auto manufacturers, including Subaru.

If you have issues with your Subaru 2.4L turbo engine or need help with a lemon law claim, the Lemon Law Experts provide a free, no-obligation consultation to evaluate your situation and offer the support you need.