Can a Bad Catalytic Converter Cause Overheating? (Explained)

A catalytic converter prevents the pollutants and toxic gasses produced by the engine due to the combustion of fuel from mixing into the environment. It does so by converting the toxins in the exhaust gas to less harmful byproducts.

Since a good catalytic converter is a very essential part of a vehicle, you might be wondering if a bad catalytic converter can cause overheating. Let’s find out if a car’s engine can overheat due to a bad catalytic converter.

Can a bad catalytic converter cause overheating?

A bad catalytic converter eventually leads to overheating. This is because it traps exhaust gas and reduces airflow to the engine. The backpressure within the engine will also increase due to a bad catalytic converter, which will significantly increase the engine’s temperature and cause overheating.

A bad catalytic converter will most definitely cause overheating. The engine of the vehicle won’t be able to cool down properly if the catalytic converter is defective.

A catalytic converter basically converts toxins in the exhaust gas to water vapor and carbon dioxide. Its main functions are to prevent toxic gasses from getting into the environment and release less harmful byproducts with exhaust gas.

The exhaust gas of the engine gets trapped in the engine because of a clogged or bad catalytic converter. As a result of which the temperature will increase and cause overheating. 

The airflow into the engine also reduces if the catalytic converter is bad. If enough air doesn’t get into the engine it won’t be able to cool down on itself and it will overheat. 

Then again, because of the reduced air passage into the engine, the oxygen level in the engine will also be low. If there is a low amount of oxygen in the engine, it will work hard which will generate more heat, eventually causing overheating.

If there is a problem in the catalytic converter of a vehicle, the back pressure within the engine will significantly increase. As a result of the increased backpressure, the temperature of the engine will rise and it can result in overheating.

Other than overheating, a bad catalytic converter will cause smoke and bad gas mileage. The defective catalytic converter will release gas that can be harmful to the environment. As a result, you should fix a bad catalytic converter as soon as possible.

How does a clogged or bad catalytic converter cause overheating?

A clogged or bad catalytic converter can cause overheating due to various reasons. A defective catalytic converter can overheat both the engine and the converter itself. 

A catalytic converter mainly transforms the toxic gasses in the exhaust gas into byproducts that are less harmful. It transforms gasses like carbon monoxide, nitrogen oxides, and hydrocarbons into water vapor and carbon dioxide. 

When the catalytic converter becomes clogged or bad, the exhaust gas will get trapped inside the vehicle. As a result of the trapped gas inside the engine, the temperature of the engine will increase massively, which will eventually cause overheating.

If the catalytic converter gets clogged, the airflow to the engine will also reduce. When the air passes to the engine, the hot and humid air from the engine comes out, which reduces the engine’s temperature. But, since the airflow reduces due to a bad catalytic converter, the engine won’t be able to release the hot air, resulting in overheating.

The oxygen level within the engine will also reduce due to the shortage of air inside the engine. The lower the oxygen level in the engine, the harder it has to work to generate speed. An engine will generate more heat if it has to work harder, which will cause overheating.

When the catalytic converter is bad, the backpressure in the engine will increase. When the backpressure within the engine increases, the temperature will hugely increase and it can result in overheating.

What are the signs of overheating catalytic converter?

There are various reasons for your catalytic converter to overheat. That being said, by knowing the signs, you can easily find out if your catalytic converter is overheating. It is very important to know the signs so that you can fix the catalytic converter when it starts to overheat.

Have a look at the signs of overheating catalytic converters.

Engine misfires:

One of the most common signs of overheating catalytic converters is engine misfire. The catalytic converter gets overheated mainly because of a defective converter. 

In that case, the engine won’t function properly due to high back pressure and shortage of oxygen in the engine, which will cause it to misfire.

Check engine light turns on:

When the catalytic converter starts to overheat, the check engine light of the vehicle turns on. This is due to the fact that when there is a fault in the catalytic converter, the amount of air in the engine will be less. 

In that case, the air-to-fuel ratio sensor will make the check engine light turn on.

Increased carbon emissions:

When the condition of the catalytic converter in a vehicle is bad and overheating, the carbon emission will increase massively. In this case, you should immediately replace the catalytic converter as soon as possible if you don’t want it to damage the exhaust system. 

What happens when a catalytic converter overheats and gets too hot?

When a catalytic converter overheats and gets too hot, it won’t be able to convert the toxic gasses in the exhaust gas to carbon dioxide and water vapor. So, when a catalytic converter gets too hot, it will release toxins and pollutants along with the exhaust gas.

The carbon emission from a vehicle will also increase due to an overrated catalytic converter. When the catalytic converter gets too hot, the engine will also not be able to function properly, reducing the acceleration power.

How to fix overheating catalytic converter?

Fixing an overheating catalytic converter is not as difficult and complicated as it may seem at first. You can do it quite easily if you follow the tips and correct methods. 

You will have to do it in the right way and as soon as possible to prevent the vehicle from sustaining permanent damage.

Have a look at how you can fix an overheating catalytic converter.

Replace a bad spark plug:

If there is a worn out or bad spark plug in your engine, it will dump hot unburnt fuel into the cat converter. The hot fuel will overheat the catalytic converter. So, you can prevent the catalytic converter of your vehicle from being too hot by changing the spark plug that is defective.

Service the engine:

One of the major reasons for a catalytic converter being overheated is because of unburnt fuel coming out of the engine. This usually happens when the engine is malfunctioning. 

By servicing the engine and changing the engine oil, you can make sure the mechanism of the engine goes on perfectly.

Replace the catalytic converter:

A catalytic converter will overheat when it gets clogged and defective. If the cat converter gets clogged, the exhaust gas will impose more pressure on the converter while being released, which will increase its temperature. 

So, you can fix an overheating catalytic converter by replacing the converter itself. 

How to prevent the catalytic converter from overheating?

You can prevent the catalytic converter from overheating with a little bit of effort and time. It is much simpler and easier than fixing an overheated catalytic converter. 

Let’s take a look at how you can prevent a catalytic converter from overheating.

Service the engine regularly:

The catalytic converter will get overheated when the unburnt fuel from the engine is released into the cat converter. This will happen if there is an issue with the engine. 

So, if you maintain your engine properly and on a regular basis, you can prevent the catalytic converter from being overheated.

Replacing worn out spark plugs: 

When the spark plugs get worn out, they will fail to ignite the fuel properly. So, hot uncombusted fuel will come through to the catalytic converter, which will make it too hot. 

As a result, by changing the worn out spark plugs, you can prevent the cat converter from being overheated.

Monitoring oil consumption:

A catalytic converter will get overheated when there is an issue with it. If the cat converter is clogged or defective, it will become too hot. The fuel performance of the vehicle becomes bad when the catalytic converter is bad. 

So, by monitoring the oil consumption of a car you can prevent the catalytic converter from overheating.

Final Thoughts

A bad catalytic converter will make it too hot. The catalytic converter overheats mainly because the backpressure within the engine increases at a huge rate when it is defective. A clogged catalytic converter will also halt exhaust gas from coming out of the engine, which will cause it to overheat.