How long should a Subaru catalytic converter last?

Most Subaru catalytic converters are expected to last roughly 100,000 to 150,000 miles (160,000 to 240,000 kilometers) under normal driving conditions. With careful maintenance and favorable driving habits, some can go longer; with engine issues or damage, they may fail sooner.

What determines the life of a catalytic converter

Several factors influence how long a Subaru’s catalytic converter remains effective. The following points highlight the main influences from engine health to driving patterns.

• Engine health and maintenance: Misfires, fuel-rich or lean runs, and failing oxygen sensors can overheat or contaminate the catalyst, shortening its lifespan.


• Driving habits: Frequent short trips without letting the exhaust reach its operating temperature can reduce catalyst efficiency over time.


• Fuel quality and emissions-system condition: Contaminants and degraded sensors can impair catalytic performance.


• Exhaust-system integrity: Leaks, damaged heat shields, or impact damage can alter catalyst temperature and function.


• Catalytic-converter configuration: Some Subaru models use dual-converter (two-cat) setups or pre-cats, which can affect overall longevity and replacement cost.


• Environmental and use conditions: Harsh climates, road salt, and heavy highway use can influence corrosion and wear.

Understanding these factors helps Subaru owners anticipate maintenance needs and avoid unexpected failures.

Model and engine differences in Subaru lineup

Subaru's engine designs and emissions layouts vary by model and year. Some models employ multiple catalytic converters or specific placements to meet emissions rules, which affects replacement considerations.

• Non-turbo boxer engines (common in many Impreza, Forester, Outback, and Legacy models) often use a primary catalytic converter plus a secondary converter near the exhaust path.


• Turbocharged models (such as WRX and certain STI variants) may have additional catalysts and more complex exhaust routing to satisfy stricter performance and emissions targets.


• Design changes over model years can shift the number and location of catalysts, influencing service intervals and costs.

When evaluating a Subaru for purchase or service, verify the exact catalytic-converter configuration for your specific year and model, since designs can differ significantly.

Common signs of catalytic converter failure

Electronic indicators

Before a converter fails outright, the vehicle’s emissions system will often reveal issues through diagnostic signals or codes.

• Check Engine Light with codes such as P0420 or P0430, indicating catalyst efficiency issues.


• Reported misfire-related codes or sensor faults that point to emissions-system trouble.

If these codes appear, have a qualified technician diagnose whether the catalytic converter is the root cause or if a sensor or injector issue is contributing to the problem.

Physical and performance indicators

Other signs focus on how the car feels and sounds while driving.

• Loss of power or acceleration, especially at higher speeds, and reduced fuel economy.


• Rattling or banging sounds from under the vehicle, which can indicate a broken substrate inside the converter.


• Unusual exhaust odors (such as rotten egg or sulfur smell) or visible exhaust anomalies.

These symptoms warrant a professional inspection to determine if the catalytic converter is failing or if another component is contributing to the issue.

Tips to extend the life of your Subaru catalytic converter

Adopting good maintenance practices and mindful driving can maximize the catalytic converter’s life and help avoid premature failures.

• promptly fix engine misfires and replace faulty oxygen sensors or other emissions components as recommended.


• Use high-quality fuel and address fuel-system contamination or water-in-fuel issues quickly.


• Keep the exhaust system intact, with secure hangers, no leaks, and protection against road debris or corrosion.


• Drive on longer trips occasionally to allow the catalyst to reach and maintain proper operating temperature.


• Follow Subaru’s service intervals for emissions-related components and have the exhaust system inspected during major service visits.

These practices help maintain catalytic efficiency and reduce the risk of premature failure.

What to do if your catalytic converter needs replacement

If testing confirms catalytic-converter failure or damage, replacement is typically required. The approach and cost depend on the exact model and whether there are one or two converters.

• Cost ranges: Replacing a Subaru catalytic converter generally runs from about $1,000 to $3,000 or more, depending on the model, whether the converter is single or dual, and labor rates. Aftermarket replacements are often cheaper than OEM parts.


• Single-cat vs. dual-cat setups: Vehicles with two catalytic converters cost more to replace due to extra parts and labor.


• Installation considerations: Choose a shop experienced with Subaru exhaust systems to ensure proper fit and emissions compliance.


• Warranty considerations: Some vehicles may have emissions-component warranties; verify coverage with the dealer or manufacturer.

Before approving replacement, obtain a clear diagnosis and a written quote, and consider whether upgrading to an aftermarket or OEM converter best fits your vehicle’s age, mileage, and ownership plans.

Summary

In most Subarus, a catalytic converter should last around 100,000 to 150,000 miles under normal operation, with lifespan extending for well-maintained engines and steady driving. Life can shorten due to engine problems, fuel issues, or physical damage. Staying on top of maintenance, addressing sensor or misfire issues promptly, and choosing the right replacement option can help maximize longevity and minimize cost.

Can a catalytic converter last 200,000 miles?

Yes, a catalytic converter can last 200,000 miles, and often lasts for the life of the vehicle, but this depends heavily on the car's condition and how it's driven. While many are designed to last between 70,000 and 100,000 miles, they can go much further, or fail prematurely due to issues like engine misfires, oil leaks, or extensive short-trip driving. 
Factors that can extend a catalytic converter's life

• Highway driving: Consistently driving at highway speeds allows the converter to reach and maintain its optimal operating temperature, which is more efficient. 
• Good engine maintenance: A properly running engine, free of misfires or internal leaks, prevents contaminants from damaging the converter. 
• High-quality fuel: Using the correct, high-quality fuel can help prevent issues that lead to premature failure. 

Factors that can cause a catalytic converter to fail prematurely

• Frequent short trips: Short, stop-and-go trips mean the engine and converter don't get hot enough to operate efficiently, leading to faster wear. 
• Engine problems: Issues like a misfiring engine, a leaky head gasket, or internal oil leaks can send unburnt fuel and oil into the exhaust, which can damage the converter. 
• Physical impact: Road debris or road impact can damage the internal structure of the converter, causing it to fail. 
• Corrosion: Although age isn't the primary factor, corrosion can lead to failure over time. 

Signs that a catalytic converter may need replacement

• A "Check Engine" light comes on.
• Reduced engine performance, power, or acceleration.
• A rattling noise from the exhaust.
• A rotten egg or sulfur smell from the exhaust.
• Failing an emissions test. 

How much is it to replace a catalytic converter on a Subaru?

A Subaru catalytic converter replacement can cost anywhere from \$300 to over \$3,000, depending on the vehicle, parts, and labor. The main factors are the cost of the part itself, which can range from around \$195 to over \$2,600 for genuine Subaru parts, and labor costs, which typically range from \$130 to \$300 or more depending on the shop's rates and the complexity of the installation. 
Cost breakdown

• Parts: The price of the catalytic converter varies significantly based on whether you choose an aftermarket or OEM (Original Equipment Manufacturer) part. 
  • Aftermarket: Can be as low as \$195 and are a more budget-friendly option. 
  • OEM: Genuine Subaru parts are more expensive, with some specific converters costing over \$2,600. 
• Labor: This can range from about \$70 to \$130 per hour, but the total cost depends on the specific Subaru model and the complexity of the job. Some shops may quote a flat labor rate for the replacement. 
• Other potential costs:
  • Oxygen sensors: It is often recommended to replace the oxygen sensors at the same time as the catalytic converter, which will add to the total cost. 
  • California-approved models: If you live in a state that requires California emissions standards, the replacement converter may be more expensive. 

Factors that can influence the final price

• Model and year: The price of the catalytic converter is specific to the vehicle's make and model. 
• Parts choice: Choosing an OEM part is more expensive than an aftermarket part. 
• Labor rates: Labor costs will vary by shop, so getting multiple quotes is recommended.
• Emissions standards: California-specific models may be more expensive to replace. 

Tips to save money

• Get multiple quotes from different shops, including independent mechanics and muffler shops, for both parts and labor. 
• Consider aftermarket options to lower the cost of the part. 
• If your Subaru is older, you may want to have the vehicle inspected to see if it's possible to replace the sensors or repair the exhaust system to avoid replacing the entire catalytic converter. 

How long does a Subaru Outback catalytic converter last?

Catalytic converters are supposed to last you up to 100,000 miles. All of them have warranties of up to 50,000 miles or five years, whichever came first. So yours might not be under warranty anymore but it breaking down is abnormal.

Do subarus have catalytic converter issues?

If your Subaru feels sluggish or less responsive than usual, particularly when accelerating, it could indicate a problem with the catalytic converter. A clogged or damaged converter can restrict exhaust flow, leading to decreased engine efficiency and performance.