A catalytic converter regulates the tailpipe emissions of your vehicle but may leave the car owner struggling when it comes to evaluating pricing for the replacement catalytic converter.
If your catalytic converter is missing or just broken, be ready to face replacement cost between $200 and $2,500, plus labour fees.
Edmunds offers some valuable pricing options that reflect the very dynamic market represented by scrap yards representing the used catalytic converters, and the discrepancies of regional pricing and the volatile precious metals market.
We also provide some high-level guidance on pricing scrap catalytic converters, but please understand that our recommendations are only a reference based on very little data.
To get the most accurate reference, check with your local auto mechanic or local scrap yard, manually give them a call or email, and ask them how much they charge for catalytic converters.
In this article, we will discuss what to look for in a failing converter, the causes of a failed converter, and the replacement costs you could incur if you need to put a new one in your vehicle.
What is a Catalytic Converter?
The catalytic converter is an important part of the vehicle exhaust system. As we mentioned earlier, a catalytic converter assists in reducing hazardous air pollutants released into the atmosphere by converting harmful burning gases into less harmful exhausts like water vapor and carbon dioxide.
Conversion of hazardous exhaust gas is achieved by running various chemicals and metals through the catalytic converter that will affect various reactions to convert harmful emissions into materials that would otherwise be harmless but are now safe. Let’s go deeper into the catalytic converter.
What Does a Catalytic Converter Do?
Catalytic converters are man-made chambers (catalysts) that help reduce the harmful molecules released from an engine’s exhaust and convert them into harmless steam. It is intended to break down the combination of harmful molecules within the gases that a vehicle emits prior to it being released into the atmosphere.
Like other car parts, the catalytic converter is located under the car. The shape and structure of the catalytic converter resemble a metal box. There are two pipes attached to the catalytic converter.
The two pipes and the catalyst are used when the catalytic converter makes the harmful gases safe for human consumption by sending the gases into the environment.
The gases enter the “input” pipe, which connects to the engine of the car. The gases enter the converter and are shot over the catalyst, which burns through the chemicals making up the pollutants.
Now, to exit the catalytic converter, we have less harmful gases–these gases leave using the second pipe called the “output” pipe, which connects to the tailpipe of the car.
The main purpose of catalytic converters
Catalytic converters are parts of an automotive system designed to limit harmful pollutants created by an engine’s exhaust gases and make it more environmentally friendly.
Its reliability and efficiency are critical for the functioning of a vehicle and the continuing quest to reduce unwanted pollution in the environment.
How Does a Catalytic Converter Work?
Two catalytic events happen while exhaust gases flow through a heated catalytic converter.
- The reduction catalyst is the first catalytic activity. The reduction catalyst reduces harmful nitrogen oxides by breaking the nitrogen oxides down into separate nitrogen and oxygen molecules (the nitrogen element is captured in the converter, while oxygen is allowed to continue).
- The second catalytic event is the oxidation catalyst, which burns the unburned hydrocarbons and carbon monoxide with the metal catalyst on the converter.
In a way, catalytic converters are filters that truly destroy “poisonous” exhaust constituents, such as fumes. Catalytic converters reduce emissions, but it also influences the performance of the vehicle – for example, improving efficiency.
If the vehicle is run correctly, it will help to maintain the life of a catalytic converter and reduce the chances of unnecessary and costly catalytic converter repair or replacement.
Signs of a Bad Catalytic Converter
Below are some common signs of a bad or clogged catalytic converter.
#1. Rotten Egg Smell From Exhaust.
If you smell a rotten egg smell, this is also a sign of catalytic converter issues. This is the only gasoline engine to make the list, as a gasoline engine has a very small amount of sulfur, which turns into hydrogen sulfide when consumed as fuel.
The purpose of the catalytic converter is to get rid of harmful hydrogen sulfide and turn it into less harmful sulfur dioxide. If it is bad, some raw gas makes it through hydrogen sulfide from the exhaust of the car, and you have the rotten egg smell.
#2. “Check Engine Light” is On.
If the information from the catalytic converter is not right, the “Check Engine Light” will be on. Oxygen sensors are part of modern vehicles, and these sensors can monitor the function of the catalytic converter by measuring the exhaust gases.
If the vehicle is emitting exhaust gases with incorrect catalysis performed by the cat, the “Check Engine Light” light will be on because of those heavily worn-out oxygen sensors to tell the drivers that something is wrong. However, there are so many possibilities of things that are wrong that the driver will not be able to determine where the issue is.
This issue can be fixed by checking the trouble codes of the vehicle from a diagnostic scan tool; P0420, P0421, and P0430 are the most common fault codes that point to catalytic converter failure.
#3. Sluggish Acceleration.
Sluggish acceleration — a common sign that your vehicle has a clogged catalytic converter is lack of engine performance (notable when trying to accelerate quickly; i.e., passing in high-speed environments).
Inside a catalytic converter, the catalyst core is made with a fine wall matrix creating a honeycomb pattern. Too much carbon build-up and the converter internals can melt, with the fuel creating a lot of heat causing incomplete blockage.
Even with a small restriction in the exhaust flow, it can cripple engine performance. So with a blocked catalytic converter, you will feel it in lost performance when you accelerate, go up a hill, or are towing a weight.
In the case of clogging caused by carbon deposits, there is a chance of cleaning the catalytic converter and getting it working again.
#4. Failed Emissions Test.
Most areas of the United States require your car to pass a smog test every couple of years to make sure your vehicle burns fuel properly and keeps poisonous gases out of the air. A failed catalytic converter can be just as relevant to failing a smog test as well.
They can be tested through the OBD2 port for vehicles made after 1996, or through a hose on the tailpipe measuring poisonous gas concentrations for vehicles made prior to 1996.
#5. Rattling Noise.
If your catalyst substrate honeycomb structure has pieces broken or has been exposed to so much heat, you will likely hear a rattling sound while the engine is idling or cruising. This rattling sound is most often heard at ignition.
The catalytic converter (as part of the exhaust system) should be removed immediately, as all the loose pieces can fall down the exhaust pipe and possibly get trapped in the muffler; causing all exhaust flow to be blocked and thus creating problems with stalling and a non-operational vehicle.
#6. Reduced Fuel Economy.
Do you feel as though you are going to the gas station a lot more than you have previously? The probable answer is yes, especially since a bad catalytic converter is generally associated with poor fuel economy.
Your vehicle’s engine uses O2 sensors to control the fuel/air mixture in the engine’s combustion chamber.
If there is a blockage causing pressure in the exhaust system, the O2 sensors are not getting accurate readings that tell them how much air is going into the system. The result is that the engine is sending excess fuel to the fuel system that it, in turn, cannot use.
Running rich is the term, and not utilized to the amount of fuel that the catalytic converter is already blocked from all exhaust gases.
Causes of Catalytic Converter Problems
Physical Damage
In today’s vehicles, there is one to three catalytic converters mounted underneath the vehicle, sandwiched between the engine and the muffler (roughly at the foot well or under the front seats). This area is susceptible to damage due to driving over curbs or road debris, which can potentially harm the muffler or tailpipe too.
Most of these issues remain hidden until they are inspected on a car lift (say, during an oil change). (To add, the sheet-metal heat shield that surrounds the converter can become loose and rattle, but this is not an issue with the converter itself).
In principle, crushing the catalytic converter will destroy the device, but other types of indirect damage can also damage the device. For example, damage to the tailpipe and muffler can increase back-pressure on the exhaust system, which can then increase the temperature in the catalytic converter.
Overheating
In all vehicles, the catalytic converter is intended to convert harmful pollutants like unburned gasoline and nitrogen oxides into safe gases. If a vehicle is fed too much unburned gasoline, it can lead to overheating the converter, which can burn the inside of the converter.
As an example, a plugged or damaged muffler can create an exhaust restriction which both cases can lead to a catalytic converter being overheated, and in the worst-case scenario, the carpet that is outside of any vehicle and above the catalytic converter or below the car and on the grass can ignite.
Clog or Contamination
Bad Oxygen Sensor, Bad air filter, engine oil seepage via piston rings or valve guides, burnt air-fuel mixture in the cylinder because of a blown gasket in the head could create contaminated coolant in the exhaust.
Most engine misfiring that’ll be caused by either fueling issues or bad spark plugs is bound to trigger the engine warning light, however, the problem most often is very similar to a faulty system that can be diagnosed.
Generally, there’s no mechanical evaluation upon no signs of a malfunctioning head-gasket, an old piston ring, damaged valve guides, etc.
When coolant leaks into the exhaust system, it usually gives off white exhaust smoke — burning oil gives blue smoke or gray smoke; Exhaust smoke as a result of a rich mixture gives black smoke, too much gasoline.
While a driver will not detect exhaust smoke as much while idling, they are typically more noticeable while driving – so the driver may not see the exhaust issue until its very bad or detrimental. Taking a while to check exhaust outlet occasionally after warm up will be good.
In cold temperatures especially the exhaust will usually look white initially, at least in part because of water in the system combusting after a while.
No matter what the issue is, the check-engine light is probably going to trigger a warning; people tend to ignore this warning because the engine can appear to run normally.
That’s not the best common-sense approach, for some issues if the light’s triggered, can be minor issues like if a gasoline cap was left loose after fill-up, or bad spark plugs will still be an easy fix now but could have huge consequences if they are later ignored — like having to replace catalytic converter.
Age or Mileage
If nothing else damages them, catalytic converters should exceed a decade without failure, but like all parts, they will eventually fail.
How Much Does a Catalytic Converter Replacement Cost?
A catalytic converter’s replacement cost is usually prefaced with panic and annoyance based on how wildly inconsistent the price is. Most of the differences depend upon if it is a direct fit or universal fit unit. For many models, a muffler shop will happily install a universal replacement converter for $2-300.00.
The process is undertaken in a straightforward manner: cutting the old out from the exhaust tubing, then welding or clamping in a new unit. On many new models, the converter is often part of either a complex downtube from the engine or integrated into the exhaust manifold itself which leads to more costly possibilities – direct-fit converters only.
There are getting to be more instances of these converters as they are often referred to the add-on units, using flanges to attach and then replace them new unit. Due to their heavily designed, highly unique direct-fits typically cost more than universal models.
For direct fit options, a replacement could ring in anywhere from $300 to $2500 for the actual part alone. Include labor, usually on average $70 to $130 an hour, for installing the converter. The actual time to install depends on the vehicle.
If you do the work, you are not paying for labor. However, the actual cost of the catalytic converter is usually the highest part. Although it does take time doing the work, it is usually not that physically demanding, especially if you purchase a direct replacement catalytic converter.
How to Prevent Catalytic Converter Theft
Because converters are made with precious metals like palladium and platinum, thieves are attracted to stealing them. Catalytic converter theft is more common in vehicles that sit higher off the ground, putting the components within reach of thieves.
To deter theft regardless of vehicle configuration, you can take the above actions:
- If you cannot access a secure garage, park in much higher, lighted areas, possibly closer to some entrances of buildings.
- Weld the catalytic converter to the frame so it becomes more difficult to remove.
- Find an aftermarket add-on to cover the converter with a metal guard.
- Install car alarms that have a vibration motion sensor option.
- Etch the last six numbers of the vehicle identification number (VIN) on the converter. This action can help deter sales of the part and assist in the theft detection of the converter.