6 Symptoms of a Bad Catalytic Converter and Replacement Cost

In this article, we will talk about the basic functions of a catalytic converter, bad symptoms and the average replacement cost. If you look underneath the car, you will find this part in the middle of the exhaust pipe. And to know more about catalytic converter, you can read full article below:

Basic Functions of a Catalytic Converter

Exhaust gas contains toxic pollutants in it. To reduce the level of toxic pollutants in it, an emissions control device called a catalytic converter is used and causes a redox reaction. Internal combustion engines contain catalytic converters in them, as long as they’re powered by either diesel or petrol fuel. You may also find catalytic converters in kerosene stoves, kerosene heaters, and lean-burn engines.

How the Catalytic Converter Works

Catalytic converters have between 1 to 2 sections, which are known as beds. These beds have certain catalyst elements in them which operate at a minimum of 400°F, causing certain kinds of chemical reactions. These chemical reactions have the ability to convert dangerous exhaust gases, like NOx, HC, and CO, into gases that are not so harmful, like N, H2O, and CO2. These less harmful gases are what end up getting released from the exhaust pipe of your vehicle.

Bad Catalytic Converter Symptoms

Below are 6 common symptoms of a bad catalytic converter:

1. “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 air fuel/oxygen ratio 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 “Check Engine Light” can mean a lot of different things. The best thing to do is retrieve the trouble codes from the vehicle by scanning it for them. This will let you know exactly what the issue is.

2. Engine Poor Power

The most common symptom of a bad catalytic converter is a lack of power in the engine, particularly when you try to accelerate the vehicle. The exhaust system of the vehicle contains the catalytic converter, which is why the engine’s performance is affected when the converter experiences problems.

3. Fuel Economy is Low

A failing catalytic converter means that fuel use will be impacted by the exhaust process. It is hard to detect small drops in your miles-per-gallon but if the highway MPG drops more than 10%, then there is a problem. For example, if a vehicle gets 35 highway MPG and it drops to under 32 MPG, then the catalytic converter is likely to blame.

4. Unusual Odors from the Exhaust

If strange odors are coming from your exhaust, this could mean you have a bad catalytic converter. The odor will likely be strong and consistent, which means you have a faulty catalytic converter that is probably overflowing with fuel. At this point, you should have your catalytic converter examined right away because excessive amounts of gases and heat are going to be created from this. Then, your car will not be safe for driving. Usually, these odors will come up after your vehicle loses acceleration and power. If these symptoms occur simultaneously, then it is definitely the catalytic converter at fault.

5. Rattling Noise

A bad catalytic converter could create a rattling noise, especially if the converter is internally damaged or just old. Often times, years of fuel mixing will cause the honeycomb meshes of the converter’s interior to break apart, which is why the rattling noise occurs. You’ll hear the noise when you start the car, but then the rattling will get louder as you continue to drive your car.

6. Emissions Increase

The catalytic converter may not perform properly if its internal chemical mechanisms are contaminated with substances like antifreeze or motor oil. If something like this occurs, the carbon emission levels of your exhaust will be a lot higher. This will require you to replace the catalytic converter and then repair the main area where the problem started. If you don’t fix this source, your whole exhaust system will get damaged and then emit large amounts of emissions that will rise into the atmosphere. There are laws against emitting too many emissions, so you could get in legal trouble if you let this problem continue.

Catalytic Converter Replacement Cost

It won’t be cheap to replace the catalytic converter. Vehicles made prior to 1981 may cost anywhere from $100 to $600 for a catalytic converter replacement. Older cars are obviously going to be more complicated to perform a replacement job on, which is why the service costs more money. It may take many hours for the replacement job to be completed. That is why you should make sure that you know how much the labor costs are going to be.

Vehicles that are made after 1981 have a 3-way catalytic converter which is more expensive than the older converter. You can expect the cost of this 3-way catalytic converter to be anywhere from $350 to $1,500. The labor costs should be between $615 and $2,200. Of course, the exact costs are going to vary depending on the exact year, make and model of your vehicle. Also, the auto body shop where you take your car is also going to be a factor of the cost too.

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If you regularly drive short distances with your car, the hydrocarbons may not be getting burnt away completely because the catalytic converter is likely not rising high enough in temperature to do so. To reduce the chances of having a clogged catalytic converter, try driving your vehicle on the highway every now and then for around 10 to 15 minutes. This will create a lot of heat from the exhaust and it will effectively burn these hydrocarbon deposits that are inside the catalytic converter.

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