What is a Catalytic Converter?

If you know anything about cars, you have likely heard of a catalytic converter. But most people have little or no idea what they are. In this article we will talk about everything you need to know about a catalytic converter.

A catalytic converter is an exhaust emission control machine that converts poisonous gases (toxins) and pollution in exhaust gas from an inner combustion engine into less-toxic pollution via catalyzing a redox reaction.

Catalytic converters are commonly used with inner combustion engines fueled by gas or diesel, along with lean-burn engines, and occasionally on kerosene heaters and stoves.

The first significant introduction of catalytic converters was in the United States car market. To comply with the U.S. Environmental Protection Agency’s stricter rules of exhaust emissions, most gasoline-powered vehicles beginning with the 1975 model year are geared up with catalytic converters. These “two-way” converters mix oxygen with carbon monoxide (CO) and unburned hydrocarbons (HC) to produce carbon dioxide (CO2) and water (H2O).

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In 1981, two-way catalytic converters have been rendered out of date by “three-way” converters that additionally minimize oxides of nitrogen (NO x ); however, two-way converters are nonetheless used for lean-burn engines. This is due to the fact three-way-converters require either rich or stoichiometric combustion to efficiently minimize NO x .
Although catalytic converters are most frequently utilized to exhaust systems in automobiles, they are additionally used on electrical generators, forklifts, mining equipment, trucks, buses, locomotives, motorcycles, and on ships. They are even used on some wood stoves to control emissions This is typically in response to authorities regulation, either via direct environmental regulation or through health and safety regulations, keeping the environment in mind at all times.

Catalytic Converter Cost – Is it expensive or Cheap?

Unfortunately, it is not affordable to replace a catalytic converter. So, how much does it cost to change a catalytic converter? While labor costs are incredibly low, the part itself is costly. This is due to the composition of the part. Your catalytic converter is costly because it needs rhodium to decrease smog levels. Rhodium, at its modern-day value, is extraordinarily high-priced which makes the usage of it in a catalytic converter expensive. To make up for their cost, manufacturers have to increase the cost of the catalytic converter. The valuable metals included in the catalytic converter are expensive, and they make the cost of the parts very high. A single new catalytic converter can range somewhere from $500 – $2,000, this depends on the make and model of your car. Labor for the job usually only costs around $100 – $300, which puts the whole cost of a catalytic converter replacement around $1,000 – $2,500 in most cases. Remember that some cars even have more than one catalytic converter. If you have an issue with your engine, it can lead to having to change all the converters.


If you should dump too much unburned fuel into the exhaust or antifreeze getting internal the combustion chamber can damage all your catalytic converters. In that case, you should be searching at a large repair bill for your car.

In summary, there is no given set price for catalytic converter replacement, though they can range from $1,000 to as high as $2,500 as at the time the article was written.

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How to know if your catalytic converter is bad

The basic symptoms of a bad or damaged catalytic converter are as follows:

1. You perceive sulfur or rotten eggs. Fuel consists of sulfates, which are characterized by that pungent rotten egg smell. A clogged cat causes gasoline to build up, making the usually undetectable smell noticeable.

2. You will hear a rattling sound coming from the under of your vehicle. A rattling sound coming from your vehicle is in no way a positive occurrence. When a catalytic converter gets bad, it can cause the honeycomb mesh interior to tear/break or collapse. When you turn on your vehicle, these pieces will vibrate and make a rattling sound.

3. Your vehicle will start to misfire. Catalytic converter problems will cause gas within your engine to start to overheat up to the point that it actually lights up in flames. This ignition is what causes the misfiring activity and that can destroy your engine components. Anytime your vehicle happens to misfire, you should have it checked out by a professional.

4. Your vehicle’s gas mileage has decreased noticeably. Experiencing pain at the pump? That, combined with other symptoms, could point to a catalytic converter failure. A clogged cat causes reduced airflow that causes your engine to burn extra fuel. Not only does this increase your fuel bill and waste gas, it makes the clog worse. To the average driver, lower fuel efficiency is one of the most noticeable symptoms of a bad catalytic converter.

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5. Your vehicle’s fuel mileage has diminished quite noticeably. If you are experiencing pain at the pump? That, mixed with different symptoms, should point to a catalytic converter failure. A clogged cat causes decreased airflow that causes your engine to burn more fuel. Not solely does this amplify your car fuel consumption and waste gas, it makes the clog worse. To the average driver, low fuel efficiency is one of the most significant signs of a worn out or a bad catalytic converter.

6. The smoke coming out of your car’s tailpipe is dark. A clogged cat makes it more difficult for exhaust to leave your vehicle, so it builds up and becomes thicker and darker when it exits the exhaust pipe.

7. Your vehicle’s check-engine light is on. When your check-engine light illuminates, and you are not sure why? “catalytic converter problem” is probably not your first suspicion. If you rule out other causes of an oxygen sensor, engine-misfire, or emissions-related code, have a mechanic check that out.

8. When you remove oxygen sensors and vehicle performance plummets. If you happen to know your way around under the hood (or better yet you know a great mechanic) you can run a test. Remove your vehicle’s oxygen sensors from the exhaust system (temporarily). If the performance worsens noticeably, that’s a sign that your catalytic converter is bad.

in summary, most catalytic converter failures fall under one of three categories: Overheated, broken or melted converters, Coated or oil-fouled substrate.

Why do people steal catalytic converters?

Money is the main motive catalytic converters are frequently stolen. Catalytic converters comprises of three metals that help in the chemical reaction that makes exhaust pollutants less harmful: rhodium, platinum, and palladium. The costs of these metallic materials have risen dramatically for the duration of the early 21st century.

Priced via the ounce, platinum went from an average of about $530 per ounce in 2001 to about $1,100 in 2021 after it reached a high of $1,700 in 2011. Palladium went from an average cost of $600 per ounce in 2001 to a fee of almost $2,400 in 2021.

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But it’s rhodium that’s been the most volatile. After averaging roughly $1,600 per ounce in 2001, it jumped to an average of about $18,000 in 2021, with a price that year of almost $26,000. By contrast, gold went from about $300 per ounce in 2001 to roughly $1,800 in 2021, a sixfold increase.

The jump in the cost of a converter’s three valuable metals outcomes in a higher price for the converter itself — and greater values for converters as scrap, as the metals can be recovered and sold.

As a result, junkyards are more actively accumulating catalytic converters, and some agencies have sprung up that will buy converters sent to them. While the cost of a given converter varies tremendously, some figures seen in advertisements from “mail-them-to-us” agencies range from about $140 to a whopping $1,500. The rise in price has triggered thieves to steal catalytic converters, regularly cutting them out from underneath a vehicle parked right on the street.

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5 Tips to keep your catalytic converter in shape are:

  1. Early detection via inspection. When servicing your car, inspect the converter. Be sure to look out for unusual noises, cracks or other damage to the external shell in the exhaust. If you notice any of these, there is a chance that the converter might be bad and needs a replacement.
  2. Never use cheap fuel! Leaded fuel can cause lead poisoning and reduce the efficiency of your converter . Always go with the recommended grade or required by your owner’s manual. Your engine would thank you too, your money too.
  3. Be slow on road bumps: When you are driving on uneven roads, be sure that your converter does not hit the group during the bumps. The heart of the catalytic converter is usually made of ceramic, which shatters easily upon impact.
  4. Avoid pot holes when driving. Catalytic converters operate at high temperatures. When it comes into contact with fluids like water e.g. when in a puddle, it cools and contracts rapidly, which can cause the substrate to break.
  5. If your acceleration feels different and your mileage exceeds 50,000km, it is a tell-tale sign that your converter’s efficiency has declined, and needs professional converter washing.

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