6 causes of a cracked catalytic converter and fix

A catalytic converter is a crucial component that helps to remove carbon monoxide and other harmful gasses that the engine produces from entering the environment.

While a catalytic converter issue will not prevent your car from functioning, you can easily land in trouble with the authorities if you drive with a damaged catalytic converter.

That is why it is important to always ensure your car’s catalytic converter is in good condition. So, have you realized that your car catalytic converter is cracked and wondering what could be the cause? If yes, then in this article, we will look at the causes of a cracked catalytic converter.

What causes a cracked catalytic converter?

The catalytic converter can crack as a result of many reasons, including old age, bad spark plugs, damaged oxygen sensors, and incorrect air-fuel mixture.

Now let’s look at these causes one by one.

1. Old age

One of the main causes of a cracked catalytic converter is old age. Cars that have clocked 100k miles are more susceptible to cracks on catalytic converters. It is very rare for a new car to have this problem unless it was a manufacturer defect.

However, as the car ages, the catalytic converter also ages, thus becoming more susceptible to cracks especially when subjected to a lot of pressure.

2. Oxygen sensor not functioning properly

The oxygen sensor plays a crucial role in measuring the number of exhaust gasses that come off from the engine. This component sends real-time data on the amount of unburned oxygen in the exhaust to the engine’s computer to help it determine the right air to fuel ratio for the engine.

When oxygen sensors are damaged, it would show an incorrect reading of exhaust gasses causing a too lean or too rich condition which is both bad for your engine.

When it is too rich, it will pile a lot of pressure on the catalytic converter causing it to crack and in the worst case cause a meltdown.

3. Bad spark plugs

Bad spark plugs that misfire or don’t fire at all can cause unburned fuel to enter the exhaust system and ignite inside the catalytic converter, causing it to crack and in some instances, cause it to melt down completely.

So, if your spark plugs are faulty and your catalytic converter has cracked, then the faulty spark plug could be the reason.

4. Out of tune engine

The engine plays a huge role in determining the condition of your catalytic converter. If your engine is out of tune, then it may cause the catalytic converter to crack.

Any time your engine is operating outside the set specifications, it causes wear and tear both to the engine and the catalytic converter, leading to cracking.

5. Excess fuel entering the exhaust

The gas that powers your car is supposed to burn in the combustion chamber only. When the gas leaves the combustion and enters the exhaust system, it lights off when it reaches the catalytic converter, creating heat that can cause the catalytic converter to break.

6. Road damage

Road damage can also cause the catalytic chamber to break. This is particularly common for motorists who drive cars with low clearance off-road.

The catalytic converter is made of lightweight thin fragile materials that can easily crack if it is knocked hard. When driving off-road, small debris striking the catalytic converter may cause it to break.

Is it worth it to fix a cracked catalytic converter?

Once you find out that your catalytic converter is cracked, you may wonder whether to repair the cracked catalytic converter or replace it with a brand new one.

A cracked catalytic converter can be fixed using a steel putty to seal the cracks. However, fixing it will only provide a short-term reprieve. If you are looking for a long-term solution, then the best thing to do is to replace the cracked catalytic converter with a brand new one.

This is the best and surest way to fix the problem. Most repair tactics that most mechanics use are usually untested and only deliver short time results.

How to fix a cracked catalytic converter?

A cracked catalytic converter can be fixed using two methods. They include sealing the cracks using a steel putty, and foam of permanent seal.

This option is cheaper but only gives short-term results. Once the catalytic converter has cracked, the crack will continue to widen over time.

That means that even if you used the steel putty to seal off the cracks, the solution will not last for long. The best solution to fixing a cracked catalytic converter is to replace it with a brand new one.

However, it is important to note that replacing a catalytic converter is not cheap. In fact, the reason why most motorists choose to use steel putty to seal off the crack is that buying a brand new catalytic converter is costly.

For most vehicles, the average cost of replacing a cracked catalytic converter is between $945 and $2470 depending on your car model. Although it is costly to replace a cracked catalytic converter, this option provides long-term results.

What does a cracked catalytic converter sound like?

When cracked, the catalytic converter will produce rattling noises that get worse over time. The rattling noise is usually the loudest when starting the car.

The rattling sounds are produced because the catalyst metal, the palladium or platinum, has been manufactured in a honeycomb pattern and usually breaks off when the catalytic converter cracks.

When the catalytic converter is cracked, a rattling sound like a stone in a tin will be heard and it will get worse over time.

Final thoughts

If your catalytic converter is cracked and you are wondering what could be the cause of the problem, we hope that this article has answered your questions.

The moment you find out that your catalytic converter is damaged, you should take it to a trusted mechanic for a thorough checkup.

This will help you know the main cause of the problem and it will be fixed to ensure that your new catalytic converter does not crack.

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