A catalytic converter is an important component in reducing your vehicle’s tailpipe emissions. But catalytic converter pricing can be daunting if you need to replace the one in your car.
Whether your catalytic converter needs replacing because it was stolen or because it is failing, a replacement can potentially cost you anywhere between $200 and $2,500 — and that’s excluding labor costs.
Catalytic converter pricing varies by location and follows the precious metals value of its components. Here are Edmunds’ estimates for what you’ll pay for a new catalytic converter, or profit off of a used one.
We also take a look at scrap catalytic converter prices. Note that what follows are simple guidelines only based on available data. Call your mechanic or local scrap yard for catalytic converter pricing near you.
Keep reading to learn the symptoms of catalytic converter failure, what causes it, and how much it will cost to replace it.
What is a Catalytic Converter?
As mentioned above, a catalytic converter is an essential part of a vehicle’s exhaust system. It helps lower the number of toxic pollutants emitted into the air by converting hazardous combustion gases into less harmful substances, like water vapor and carbon dioxide.
This is done by exposing these fumes to chemicals and metals inside the converter to prompt chemical reactions that transform otherwise toxic pollutants into relatively harmless ones. Let’s break down how a catalytic converter functions a bit further.
What Does the Catalytic Converter Do?
A purpose of a catalytic converter is to use a chamber called a catalyst to change the harmful compounds from an engine’s emissions into safe gases, like steam. It works to split up the unsafe molecules in the gases that a car produces before they get released into the air.
The catalytic converter is located on the underside of a vehicle and looks like a large metal box. There are two pipes coming out of it. The convertor utilizes these two pipes and the catalyst during the process of making the gases safe to be expelled.
Gases are brought in from the “input” pipe connected to the engine of a vehicle. These are blown over the catalyst, which causes a chemical reaction that breaks apart the pollutants.
The less-harmful gases now travel through the second pipe, or the “output,” that is connected to a car’s tailpipe.
Core purpose of catalytic converters
The core purpose of catalytic converters in automotive systems is to reduce the emission of harmful pollutants from an engine’s exhaust gases and make them more environmentally friendly.
Their effectiveness and reliability are vital not only for maintaining vehicle performance but also for contributing to efforts to reduce atmospheric pollution.
How Does a Catalytic Converter Work?
When exhaust gases pass through a heated catalytic converter, two catalytic events (chemical reactions) take place:
- The reduction catalyst is the first of the two catalytic events to occur. It uses the metal catalysts to reduce harmful nitrogen oxides by separating the molecules into nitrogen and oxygen. The nitrogen is trapped within the converter, while the oxygen passes through
- The oxidation catalyst is the second catalytic event. It reduces unburned hydrocarbons and carbon monoxide by burning (oxidizing) them over the metal catalyst.
Essentially, a catalytic converter filters out harmful byproducts in the exhaust gases and burns them up. And while the main function of a catalytic converter is to reduce harmful emissions, it also improves your car’s efficiency.
A well-maintained car will extend the life of your catalytic converter, minimizing the possibility of a costly catalytic converter repair or replacement.
Bad Catalytic Converter Symptoms
Here are 6 common symptoms letting you know your catalytic converter is clogged or bad.
#1. Rotten Egg Smell From Exhaust.
If you smell something that seems like rotten eggs, it’s a tell tale sign of a failed catalytic converter. Gasoline contains a small amount of sulfur which converts to hydrogen sulfide during the combustion process.
A catalytic converter that’s working like it’s supposed to, converts the smelly sulfide into odorless sulfur dioxide. When the cat is bad, the conversion doesn’t take place so some of the unburnt gases containing the smelly hydrogen sulfide exit your exhaust.
#2. “Check Engine Light” is On.
If your vehicle’s catalytic converter is failing or has gone bad, the “Check Engine Light” will illuminate on the dashboard. Modern vehicles contain oxygen sensors which are able to monitor the catalytic converter’s efficiency by checking the exhaust’s gas levels.
If these sensors detect the exhaust gases are not being catalyzed properly for whatever reason, the “Check Engine Light” will come on. The driver will then know something is wrong, although they won’t know exactly what the problem is because the light can mean a lot of different things.
The best thing to do is retrieve the trouble codes from the car using a diagnostic scan tool. P0420, P0421, and P0430 are two common fault codes that indicate a catalytic converter failure.
#3. Poor Acceleration.
One of the most common symptoms of a clogged catalytic converter is a lack of power from the engine, particularly when you try to accelerate such as when you need to pass another vehicle quickly.
When carbon buildup within the honeycomb design gets to be too much or when the internals start to melt due to excess heat from unburned fuel, a partial blockage inside the catalytic converter takes place.
Your engine depends on good exhaust flow to operate at peak power. When the flow is restricted due to a clogged converter, you’ll notice a lack of power when accelerating, going up a hill, or towing a heavy load.
For cases of clogging due to carbon buildup, cleaning your catalytic converter can help remove the blockage.
#4. Failed Emissions Test.
Most parts of the Unites States require your vehicle to pass a smog test every few years to make sure your car is properly burning fuel and not expelling dangerous gases into the atmosphere. One of the most common reasons for failing a smog test is a bad catalytic converter.
Depending on your vehicle, diagnostics will be done through either the OBD2 port on your car (cars made in 1996 or newer) or with a hose connected to the end of your tailpipe that directly measures levels of toxic gases (cars made before 1996).
#5. Rattling Noise.
If parts of the honeycomb material inside the catalytic converter break apart due to excessive heat or damage, you will likely notice a rattling sound coming from under your vehicle while idling or driving. The noise will often be the loudest when starting the car.
You’ll want to replace the cat as soon as possible as those chunks of dislodged material can actually make their way further down the exhaust system and into the muffler. This blockage can then cause the car to stall and even prevent you from starting your car back up.
#6. Reduced Fuel Economy.
Do you feel like you’re filling up your tank more frequently than you used to? A bad catalytic converter usually means poor fuel efficiency.
Your engine relies on O2 sensors to adequately mix oxygen and fuel – a clog can lead the sensor to believe it’s getting more air than it is, subsequently injecting more fuel than you can actually use in the process.
This is called “running rich.” It can further the buildup in a bad catalytic converter if it’s already clogged.
Causes of Catalytic Converter Problems
Physical Damage
The catalytic converter (or converters, as some vehicles may have more than one) sits underneath the car between the engine and muffler, typically under the front seats or footwells. That makes it vulnerable to being damaged if you drive over a curb or road debris, which can also damage the muffler or tailpipe.
However, the damage might only be seen when the car is up on a lift, as for an oil change. (In addition, the sheet-metal heat shield encasing the converter can get loose and rattle, but that’s not really a problem with the converter itself.)
Crushing the catalytic converter will damage it, but even crushing the muffler or tailpipe can cause indirect damage to the converter, as it will increase exhaust back pressure and raise the temperature inside the converter.
Overheating
A catalytic converter’s job is to convert pollutants such as unburned gasoline and nitrogen oxide into harmless gasses. But if the converter is fed too much unburned gasoline, for instance, it will overheat, which essentially melts the inside of it.
An exhaust restriction, such as from a clogged or damaged muffler, can do the same. Either issue can result in the outside of the catalytic converter getting very hot, which in a worst-case scenario can cause the interior carpet above it or the grass below it to catch fire.
Clog or Contamination
The inside of a catalytic converter can become contaminated by unburned gasoline — often due to an engine misfire, clogged air filter or bad oxygen sensor — or coolant that has likely leaked into the exhaust through a bad head gasket, or engine oil that has leaked past the piston rings or valve guides and is burned along with the air-fuel mixture in the cylinder.
Engine misfires due to a fuel problem or bad spark plugs will typically cause the check-engine light to come on, and the trouble can usually be narrowed down by running a diagnostic test. However, that test typically won’t uncover mechanical problems such as a bad head gasket, worn piston rings or valve guides.
Contamination from coolant leaking into the exhaust will usually cause white exhaust smoke, while burning oil will usually cause blue or gray exhaust smoke. (A rich fuel mixture, which indicates too much gasoline in the system, will cause black exhaust smoke.)
As exhaust smoke is typically more pronounced when the car is being driven than when it’s idling, a driver may not notice it until things get really bad. Periodically checking the exhaust after the engine warms up can be helpful.
Note that in cold weather, the exhaust will often be white for a short time as water that has condensed in the system gets burned off.
Whatever the cause, the check-engine light will often come on, but since the engine still seems to be running all right, people tend to ignore it.
That’s not a good idea; some problems that activate the light can be fairly minor (such as not tightening the gas cap enough after a fill-up), but others (like bad spark plugs) can be things that could be inexpensively fixed now but may cause far more expensive problems down the road — including ruining the catalytic converter.
Age or Mileage
If nothing else kills them earlier, catalytic converters can easily last 10 years or more, but they’ll eventually just go bad.
How Much Does a Catalytic Converter Replacement Cost?
Part of the scare and frustration of catalytic converters is the fact that prices for replacement vary wildly. The main difference in lies within direct-fit vs a universal fit unit. For many vehicles, a muffler shop can easily weld in a universal replacement converter for $2-300.00.
This is accomplished by cutting out the old converter from the exhaust section and welding or clamping in a new one. On many newer vehicles, the converter is often incorporated into either an elaborate down-pipe section from the engine, or incorporated into the exhaust manifold itself, and in these cases, a direct-fit converter is the only option.
Direct-fit converters are generally bolt-on items, that are replaced by unbolting the flanges that attach it and bolting in a new unit. Because they are more complex, they are often very costly compared to their universal counterparts.
For direct-fit options, a replacement can cost anywhere from $300.00 to $2,500.00, depending on the model, for just the cost of the part. You should also think about labor costs, which could cost between $70 and $130 an hour to install the converter. The time it takes to finish the job will vary depending on the specific vehicle involved.
If you do this job yourself, you will save the labor costs, but many times, the actual cost of the catalytic converter is the expensive portion. While the job can take some time, it’s often not too difficult, especially if you buy a direct replacement catalytic converter.
How to Prevent Catalytic Converter Theft
Catalytic converters are often the target of thieves because the part contains valuable precious metals. Catalytic converter thefts often happen on vehicles with more ground clearance, since it’s easier to access the part.
Regardless of the type of vehicle you have, there are some steps you can take to help prevent theft:
- Park in well-lighted areas close to building entrances if a secure garage is unavailable.
- Weld the catalytic converter to the vehicle frame, which can make it harder to remove.
- Consider buying an aftermarket part similar to a metal cage that can be installed to cover the converter.
- Install a car alarm with a vibration alert sensor.
- Engrave your vehicle identification number (VIN) to the converter, which can help make selling the part harder and help alert you if your converter is stolen.