Blog Car Issues & Diagnoses What Does a Catalytic Converter Do? (+5 FAQs)
Car Issues & Diagnoses

What Does a Catalytic Converter Do? (+5 FAQs)

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The catalytic converter is an incredibly vital part of your vehicle as it reduces the environmental impact of potentially harmful gases exiting your exhaust system. With catalytic converter theft on the rise, many drivers may question why a catalytic converter thief would target their vehicle. 

What does a catalytic converter do? 
Does your car have one
Does your exhaust gas really contain harmful emissions? 

Well, we have the answers to these questions. 

In this article, we’ll find out what a catalytic converter does, how it works, and its importance. Additionally, we’ll cover some frequently asked questions about the catalytic converter.

This Article Contains

Let’s get started.

What Does a Catalytic Converter Do?

Your catalytic converter creates a continuous chemical reaction to reduce the harmful emissions from your car. It takes the toxic gasses nitrogen oxide, hydrocarbon, and carbon monoxide — and converts them to less harmful exhaust gas with a reduced environmental impact. 

It’s housed in the middle of your exhaust system, actively converting these harmful gases into cleaner, single-gas emissions.

Your state likely has compliance laws around your vehicle emission levels, which you may violate if you have a bad catalytic converter — not to mention that your average fuel efficiency will go down, leading to reduced fuel economy. 

If you’re concerned about your fuel economy, don’t ignore the health of your catalytic converter. You can quickly get a diagnosis and an estimate for a catalytic converter replacement from your mechanic

Okay, but how exactly does a catalytic converter work? 
Let’s discuss this. 

How Does a Catalytic Converter Work?

Catalytic converters use platinum group metals such as rhodium, platinum, and palladium to act as a catalyst for their chemical reaction. The precious metal content of a catalytic converter is arranged in a honeycomb structure. After the exhaust gasses pass through the structure, your vehicle’s emission will be expelled through the exhaust system as cleaner, safer gases with less harmful compounds.

Catalytic converters reduce these three toxic fumes:

Once converted, there are three primary emissions from the tail end.
These exhaust gasses are:

Because the combustion process is never perfect, smaller amounts of more harmful pollutants are also produced in an internal combustion engine and released as toxic fumes.

It’s also imperative to note that you need to use unleaded fuel for your catalytic converter to work. Lead in conventional fuel ‘poisons’ the catalyst metals, preventing them from doing their job.

Now that we know how a catalytic converter works, let’s find out why they’re required. 

The Importance of Catalytic Converters

In 1963, the Clean Air Act was passed in the United States to help reduce the number of harmful compounds contributing to air pollution.

The National Emissions Standards Act, an amendment made in 1965 to the Clean Air Act, set the first federal vehicle emission standards. Each state has regulations that adhere to federal standards, with many states requiring that all registered cars be tested to evaluate the output of emissions from their exhaust pipe

The modern engine exhaust system helps control vehicle emission output and reduce their contribution to air pollution. The catalytic converter helps car manufacturers comply with the National Emissions Standards Act.

Now that we know how a catalytic converter works and why it’s essential, let’s discuss a few catalytic converter questions. 

5 Catalytic Converter FAQs

Here are the answers to some of your burning questions: 

1. Does My Car Have a Catalytic Converter? 

And how do we know? 

Since 1975, all fuel-burning vehicles have been required to have catalytic converters, which means your vehicle likely has one. 

But where is it exactly? 
Since your catalytic converter is part of your exhaust system, you can find it between your exhaust manifold and your exhaust pipe.  

2. Can My Car Run Without a Catalytic Converter? 

Technically, your car will still run without a functional catalytic converter, but since the converter connects to the engine, it’ll start to affect your engine. Your car won’t function well with a failing catalytic converter, let alone one that doesn’t work.

Removing your catalytic converter is not a safe or legal option, as driving without a catalytic converter is illegal in all states of the US. The Environmental Protection Agency designated it a required component in 1975 to reduce harmful pollutants in the air. If the authorities get you driving without a catalytic converter, they can fine you thousands of dollars. 

3. What are the Signs of Catalytic Converter Failure? 

The following symptoms could signify catalytic converter failure:

A. Illuminated Check Engine Light

A glowing check engine light can indicate a range of things, but it’s the first sign of something wrong. A  bad catalytic converter might trigger your oxygen sensor (O2 sensor), causing the check engine light to turn on.

B. Rotten Egg Smell

If you’re smelling sulfur or a “rotten egg” smell, it could mean that your catalytic converter is malfunctioning. The smell comes from the toxic emissions circling back into your vehicle instead of out of your exhaust system. 

C. Reduced Fuel Efficiency  

A clogged catalytic converter can reduce the amount of airflow through your engine, causing your engine to burn more fuel than usual and resulting in a noticeable drop in fuel efficiency.

D. Banging or Rattling Noises 

Drivers might hear a banging or rattling sound caused by the metal pieces of a damaged catalytic converter hitting its sides. You should have your catalytic converter checked to avoid future complications.

E. Issues Starting the Engine

A clogged catalytic converter can prevent exhaust gases from effectively escaping your exhaust system. This can result in increased exhaust pressure and causes your car to stall when trying to start the engine.

4. Why are Catalytic Converters Stolen?

The number of stolen catalytic converter cases has increased, partly because of the high prices offered for the precious metal content. A catalytic converter thief will sell the stolen catalytic converter to metal dealers or sell them as aftermarket converters.

A typical catalytic converter has 3-7g of platinum, 2-7g of palladium, and 1-2g of rhodium.

Recycling a catalytic converter can get you between $50 and $250, with some going as high as $800 to $1,500 for a hybrid vehicle’s catalytic converter.

5. Why is Catalytic Converter Replacement and Repair so Expensive?

Catalytic converter repair can cost as much as replacing a catalytic converter.

You can expect to pay between $300 to $2,500 to repair a catalytic converter because of the precious metals it contains. Since the materials are expensive, you can expect a higher repair cost. 

Deep cleaning is also another repair option. However, when there is excessive wear, catalytic converter replacement may be the only option.

A catalytic converter replacement costs around $2,000 — labor not included. Installation and labor costs will further increase the price of replacing a catalytic converter.

However expensive, when a catalytic converter replacement or repair is required, it’s a necessity for your car. 

Wrapping Up

Your catalytic converter is vital to keep your vehicle’s toxic emission levels within regulated limits. If you suspect a failing catalytic converter and can’t get your vehicle to an auto repair shop, contact AutoNation Mobile Service’s mobile mechanics. 

AutoNation Mobile Service is a convenient mobile vehicle auto repair and maintenance solution. We offer convenient online booking and competitive prices for all auto repairs.

All our repairs come with a 12-month | 12,000-mile warranty. Contact us today, and we’ll bring the repairs to you.