Honda Accord Catalytic Converter: Maintenance and Replacement

The catalytic converter is one of the most crucial components of a vehicle’s emissions control system. In the Honda Accord, catalytic converters play an integral role in reducing harmful pollutants from the exhaust. This comprehensive guide will provide an in-depth look at catalytic converters specifically for Honda Accord models.

Important Headings

We will cover the function and history of catalytic converters in Accords, different types of converters, protection against theft, identifying issues, replacement and repairs, maintenance for emissions control, upgrades, location and positioning, environmental impact, and more. With useful facts, a comparison of options, step-by-step instructions, and expert tips, this article aims to help Honda Accord owners better understand catalytic converters to optimize performance, efficiency, and longevity.

Key Takeaways

  • Catalytic converter technology has advanced over the years in Honda Accords to meet tightening emissions standards.
  • For newer Accord models, Prices for scrap and new replacement catalytic converters have steadily increased.
  • Accord catalytic converters contain valuable precious metals, making them targets for theft.
  • Proper maintenance and operation help maximize the lifespan of the Accord’s catalytic converter.
  • Aftermarket catalytic converters can provide cost savings but may need to meet OEM specifications.

The Importance and Function of Catalytic Converters in Honda Accords

The catalytic converter is part of a vehicle’s exhaust system, typically between the engine and muffler. It converts toxic pollutants in the exhaust, such as carbon monoxide, nitrogen oxides (NOx), and hydrocarbons, into less harmful emissions like carbon dioxide, nitrogen, and water vapor.

In the Honda Accord, the catalytic converter is integral in meeting emissions regulations and requirements. It helps the Accord maintain a balance between engine performance and environmental responsibility.

Some Key Functions of the Catalytic Converter in Accord Models Include:

  • Oxidation of carbon monoxide and hydrocarbons into carbon dioxide and water vapor
  • Reduction of nitrogen oxides into nitrogen and oxygen
  • Removal of nearly 90% of pollutant gases from the exhaust
  • Enabling the vehicle to pass emissions testing and comply with environmental regulations
  • Contribution to mitigating climate change by reducing greenhouse gas emissions

The first Honda Accord in 1976 did not yet have a catalytic converter. But as emissions standards tightened, especially in California, Honda introduced the technology. Since then, catalytic converters have been a crucial emissions control component in all Accord models.

Over the years, catalytic converter technology and design advancements have allowed Hondas to achieve even lower emissions while maintaining performance and efficiency.

Types of Catalytic Converters for the Honda Accord

There are a few types of catalytic converters available for the Honda Accord:

Original Equipment Manufacturer (OEM)

  • Designed specifically for the Accord by Honda
  • Meets all emissions regulations and OEM specifications
  • It can be more expensive but ensures quality and fit


  • Produced by a third-party company, not Honda
  • Often cheaper than OEM converter
  • It might not meet the same quality and emissions standards as the OEM
  • CARB-certified recommended for legality in California


  • Allow for increased exhaust flow and engine power
  • Help boost acceleration and gas mileage
  • Pass emissions tests when properly engineered
  • It is illegal in some states, like California, for street use

The optimal converter depends on your needs and local regulations. OEM converters are ideal for maintaining factory specs; aftermarket cats provide an affordable alternative, while performance types generate power gains.

Catalytic Converter in Different Honda Accord Models

Honda Accord Models 2002-2005 Catalytic Converters

The 2002-2005 Honda Accord models had a single catalytic converter. This first generation of converters helped the Accord meet the stringent emissions regulations in California and other states. The most common issues reported with these early converters are clogging and failure after high mileage. Replacement costs range from $800-$1000.

Emission Control System in the 2006-2011 Honda Accord Models

In the 2006-2011 Accord models, Honda introduced some design changes to the catalytic converter system. Many came with two smaller converters instead of one large unit. This helped improve efficiency and reduce emissions. But it also increases the cost of repairs if both converters need replacing. Expect $900-$1200 for parts and labor.

Catalytic Converters in the 2012-2017 Honda Accord Models

The 2012-2017 Accords had a main underfloor catalytic converter and a smaller secondary converter. These allowed the engine to reach optimal operating temperature faster while improving emissions control. The converters from these models fetch $250-$300 as scrap due to higher precious metal content.

Emission Control in the 2018-2022 Honda Accord Models

The latest 2018-2022 Accord models utilize advanced high-cell-density catalytic converters. They also incorporate innovations like placing the converter closer to the engine for faster light-off. Replacement costs are higher, ranging from $1200-$1600. But Honda issues a longer 8-year/80,000-mile warranty.

Accord Scrap and Replacement Costs

Model Year Average Scrap Price Average New Replacement Cost
2002-2005 $100-$150 $800-$1000
2006-2011 $150-$200 $900-$1200
2012-2017 $250-$300 $1000-$1400
2018-2022 $300-$400 $1200-$1600
2023 $350-$450 $1300-$1700

Protecting the Honda Accord Catalytic Converter from Theft

As catalytic converters contain valuable metals like platinum, rhodium, and palladium, the Honda Accord has become a popular target for catalytic converter theft. There are several effective ways to deter thieves:

  • Install a catalytic converter protection device or cage around the converter to make it harder to remove
  • Have the converter welded to the chassis or exhaust system for a permanent bond
  • Park in secure, well-lit areas whenever possible
  • Engrave your VIN onto the shell for easier identification
  • Use a converter-specific clamp, bolt, or lock to secure it
  • Install a car alarm or security system to alert you of tampering
  • Paint the shell with high-temp automotive paint to make the converter less valuable to thieves looking to resell it

Preventative measures can help avoid the headache and costs of replacing a stolen catalytic converter. Be sure to report any thefts to the police and your insurance company.

How to Identify Catalytic Converter Problems in the Honda Accord

Catching catalytic converter issues early is key to avoiding damage and expensive repairs. Here are some common symptoms of a failing catalytic converter in the Accord:

  • Decrease in fuel economy and acceleration
  • Misfiring, hesitation, or rough idling
  • Dark exhaust smoke or a strong sulfur smell
  • Rattling, shaking, or loud droning sounds
  • Glowing red converter shell or exhaust
  • Melting of nearby wiring, hoses, or components
  • Failed emissions testing or diagnostic trouble codes (DTCs) pointing to the converter

On-board diagnostics (OBD-II) scanners plug into your Accord’s computer to read trouble codes and data parameters. A digital multimeter that measures exhaust backpressure can also help diagnose converter issues.

Misdiagnoses happen if catalyst inefficiency codes are ignored or sensor failures trick you into replacing the wrong parts. Working with a reputable mechanic you trust is recommended for accurate troubleshooting.

Replacing a Faulty Catalytic Converter in the Honda Accord

When it comes to replacing your Accord’s worn-out or damaged catalytic converter, you have options:

  • Have a professional mechanic do the replacement, typically around $1,100 parts and labor
  • Purchase a quality OEM or aftermarket direct-fit replacement converter
  • Go to a muffler shop for custom fabrication and installation
  • Perform the swap yourself with some mechanical know-how and tools

If opting for a DIY replacement, use a CARB-approved converter in California, and don’t skimp on safety gear like jack stands. Allow 2-4 hours for the job. OEM converters tend to cost more but come with a warranty from Honda.

Properly Maintaining the Accord Catalytic Converter and Emissions System

The catalytic converter is an emissions control component that works with other parts like oxygen sensors, EGR valves, fuel injectors, and more. Maintaining the whole emissions system is key to maximizing the converter’s lifespan and effectiveness.

Follow the maintenance schedule in your Accord’s owner’s manual, which typically includes the following:

  • Regular oil changes
  • Replacing air, fuel, and cabin filters
  • Spark plug replacement every 30k-100k miles
  • Cooling system flushes and new coolant every 3-5 years
  • Checking exhaust heat shields and gaskets
  • Oxygen sensor replacement every 60k miles or as needed

Dirty engine oil, coolant leaks, bad spark plugs, and a misfiring engine can all contribute to catalytic converter failure. Proper maintenance goes a long way!

Upgrading the Catalytic Converter in the Honda Accord

One way to boost performance in the Accord is upgrading to a high-flow or performance catalytic converter in place of the stock factory one. Benefits include:

  • Increased exhaust flow for more horsepower
  • Better throttle response and acceleration
  • Higher fuel efficiency
  • 30 to 40% gains in engine power

Performance cats are typically stainless steel or titanium versus the mild steel of OEM converters. But remember, based on your state’s laws, high-flow cats may be illegal for street driving. Professional installation is highly recommended.

An Emissions and Power Comparison Test on Honda Accord Catalytic Converter Upgrades by Racing Beat found that a high-flow cat provided a 10+ hp increase over stock at 5,500 rpm without compromising emissions compliance. Upgrading your converter can unlock more speed and power potential in your Accord.

Location and Position of the Catalytic Converter in Honda Accord Models

In the Honda Accord, the catalytic converter is typically located on the underbody of the vehicle along the exhaust system. The exact position can vary slightly between generations and models.

In older Accords up to the early 2000s, the catalytic converter was often found next to the engine for the fastest light-off and efficiency.

Newer models may have the main catalytic converter further back, with a smaller pre-converter placed next to the engine. Some generations also have two converters in sequence.

The underbody location is safer from damage but makes the catalytic converter more vulnerable to theft. While positioning has varied, the Accord’s catalytic converter has always been carefully engineered to reduce emissions.

The Honda Accord Catalytic Converter’s Role in Environmental Protection

Honda Accord Catalytic Converter’s Role in Reducing Harmful Emissions

  • Catalytic converters cut hydrocarbons and nitrogen oxide emissions by approximately 90% and carbon monoxide emissions by nearly 80% in the Honda Accord.
  • This drastically reduces the Accord’s impact on air quality and the environment.
  • The development of three-way catalytic converters in the 1980s allowed for the simultaneous conversion of all three main pollutants in a single unit.
  • Honda quickly adopted this technology in the Accord, helping the vehicle maintain its reputation for clean and efficient performance.

The Honda Accord Catalytic Converter’s Compliance with Emissions Regulations

  • By 1996, the Accord was one of the first vehicles to meet California’s stringent Low-Emission Vehicle standards, thanks to advancements in its catalytic converter systems.
  • The Accord Hybrid, introduced in 2005, was the cleanest internal combustion vehicle ever produced.
  • As regulations on vehicle emissions continue to become more stringent worldwide, Honda’s foundational work on developing effective, durable, and efficient catalytic converters ensures the Accord will comply with environmental standards for years.
  • Recent Accord models utilize a high cell density substrate that increases the surface area inside the converter for enhanced emissions reductions.

Frequently Asked Questions

What Is the Average Scrap Price for a Catalytic Converter from a 2010 Honda Accord?

Approximately $175-$225.

Does Replacing the Catalytic Converter in a 2007 Accord Require Programming or Recalibration?

Most of the time, the engine computer will reset automatically with a direct-fit OEM or CARB-approved converter.

What Are Some Ways to Prevent Catalytic Converter Theft on My 2008 Accord?

Protective cages/shields, engraving VINs, parking securely, and installing alarms/cameras can help deter theft.

Is It Legal to Install a High-Flow Catalytic Converter on My 2001 Honda Accord in California?

No, high-flow converters are illegal for street use according to the 2001 Accords in California due to emissions regulations.

How Often Should I Get the Catalytic Converter Inspected on My 2015 Honda Accord?

Follow the manufacturer-recommended service schedule, typically every 60,000 miles or so.

What Are Early Symptoms of a Failing Catalytic Converter on a 2003 Accord?

Reduced fuel economy, misfires, rough idling, loud rattling noises, and strong sulfur smells.

Does Honda Offer an Extended Warranty on Catalytic Converters for New Accords?

Honda’s factory warranty covers the catalytic converter for 8 years/80,000 miles on 2022 models.

Is It Safe to Drive My 2009 Accord if the Catalytic Converter Needs to Be Replaced?

Driving with a bad converter is not recommended, as it can lead to further damage. Has it been replaced promptly?

How Much Does It Typically Cost to Replace the Catalytic Converter on a 2006 Honda Accord?

Approximately $900 – $1,100 for parts and professional installation.

Where Is the Catalytic Converter Located on a 2013 Honda Accord?

It is on the underbody, attached to the exhaust system between the engine and muffler.

How Often Should the Catalytic Converter Be Replaced on a Honda Accord?

They typically last 100k miles or more. But issues like oil burning can shorten lifespan.


The catalytic converter has been an essential emissions control technology in the iconic Honda Accord for over four decades. From governmental regulations to environmental responsibility, the catalytic converter enables the Accord to strike an optimal balance between power, efficiency, and clean operation.

This guide covers the integral role converters play in the Accord powertrain, maintenance tips, troubleshooting techniques, replacement options, upgrades, and more. As emissions standards evolve, so too will the catalytic converter. Honda will continue innovating to meet the demands of both consumers and our planet for generations of Accords to come. The converter will keep your Accord running cleanly and efficiently with proper care and attention.

I am Nicolas, an automobile engineer with over 5 years of experience in exhaust systems and catalytic converters. I am passionate about learning and understanding how things work, and I am always looking for new ways to improve the performance and efficiency of automotive exhaust systems. Know more about me. As an Amazon Associate, we earn commission from qualifying purchases.

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