Catalytic Converter Making Noise- Easy Fixing Tips

Catalytic converter making noise HOW TO FIX
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A car has many different components that perform various activities in it, for example, the catalytic converter that works to reduce vehicle emissions and pollution to protect the environment. The catalytic converter is found in the exhaust system since it is a metallic thing that you fix in the exhaust system. The catalytic converter reduces pollution by converting the vehicle’s emissions into non-harmful products since it has the catalyst to restore the chemicals.

Therefore, when the converter is working hard to convert the harmful environmental substances, at some point, it will start making some unusual noises that you will need to fix the problems in the converter. When driving the car, you can notice if the catalytic converter is wrong and is making noise since it has been signed to show that. So you need to know the signs of a bad catalytic converter before finding how you will fix them to reduce the noises.

The article below shows the signs of a bad catalytic converter that makes the noises in it. It will then explain how you will reduce the noises in the catalytic converter with the steps you will follow. Then later are the frequently asked questions, and lastly, the conclusion.

How to reduce noise from a catalytic converter

catalytic converter making noise

After getting the possible causes of the noises in the catalytic converter, you can now check on solutions to curb the noises. Below are the steps to follow when working to reduce the noises from the converter.

Tools needed

  • Sodium hydroxide, Lacquer Thinner or High Octane Fuel and Fuel Additives for cleaning.
  • Spray bottle
  • Hose
  • Sandpaper
  • Screwdriver

1) Cleaning Your Catalytic Converter

One of the easiest methods of quieting and restoring a catalytic converter is to clean it. Over time, buildup in the cat can cause a blockage of airflow, resulting in unwanted noise and poor performance. These cleaning methods will allow you to breathe new life into your old converter without spending a fortune replacing it.

Ensure you use Sodium Hydroxide to clean the catalytic converter with sodium hydroxide; you’ll first need to remove it from the vehicle. Then, soak the inside of the converter using a spray bottle. Make sure to spray into the cat from both sides.

Let the cat sit for 20 minutes or longer, so the chemicals have time to work. After letting the chemicals work their magic, you’ll need to rinse it out properly. You can use a hose for this, but be sure to be very thorough. Again, make sure to rinse from both sides.

2) Fix Catalytic Converter Heat Shield

If the heat shield is missing bolts or has become loose, it can cause excess noise while the car runs. To fix this, you’ll first need to remove the heat shield. It can be done by removing a few bolts. You may need to use some penetrating oil since the high heat can cause the bolts to be quite stubborn.

Once removed, thoroughly wash the cat with soap and water. If the inside is hazy, you can polish it with high-grit sandpaper to ensure maximum heat reflection. Before reinstalling the heat shield, add some anti-seize compound to the bolts. Make sure to tighten them to the proper torque specifications.

3) Replace a Catalytic Converter

The process of replacing the converter includes following the right steps and ensuring you have the right tool to use. The exorbitant cost of replacing a catalytic converter can cause many people to wonder if it’s something they can replace themselves.

Luckily, it’s not that complicated of a fix. That said, make sure to purchase a direct fit converter that’s meant specifically for your vehicle, not a universal fit. A universal cat will require welding, while a vehicle-specific converter will be installed with bolts.

What shows that a catalytic converter is bad?

What shows that a catalytic converter is bad?

1. Rattling noise

 The number one sign a catalytic converter has issues with is the rattling noise from it. If your converter produces the rattling noise, it shows something wrong that you need to fix immediately before it causes other damage.

The rattling noise results from a loose heat shield. When the converter is rattling, consider checking the heat shield that when it is open, it will cause the noises.  The heat shield becomes loose when one of its bolts becomes loose and is broken, which causes the complete protection to be flexible.

The other cause of rattling noise in the catalytic converter is the ceramic honeycomb structure that tends to break apart—the ceramic breaks due to wear and tear over time when using it.  When the ceramic honeycomb gets damaged, you can fix it but instead install a new honeycomb in place. You will need to struggle when determining the exact location causing the noise.

2. Poor performance of the engine

Poor performance of the engine

When the catalytic converter is wrong, the performance rate will be slower than the engine, too will fail to work correctly. The catalytic converter is in the exhaust system so that when it fails to work, it can affect the machine and cause other problems.  The converter can have dirty particles that accumulate and prevent the flow in the exhaust, while the one with cracks can leak poisonous fumes. Both two issues with the converter can cause effects on the engine.

3. The rotten egg smell from the exhaust system

 When a catalytic converter has issues, you will smell a rotten egg from the combustion gases since they contain sulfur. If the converter is working correctly, you need to hear a good smell since its purpose is to convert the bad smell to an odorless odor.

4. Lights from the engine are on

When the catalytic converter has issues, you will notice some light in the engine area. The light works by alerting the car driver to check on the problems with the converter and change them.

5. Poor emissions tests

When the vehicles produce harmful substances, it shows that the converter is not performing its function since its main role is to convert the toxic substances to nontoxic substances that cannot cause effects the environment.

Frequently asked questions:

  • What can you use to clean the catalytic converter apart from the sodium hydroxide?

There are two other components you can use to clean the catalytic converter. The components include:

1. Lacquer Thinner. Lacquer thinner can be an effective tool for cleaning out an old cat or one that’s just losing efficiency. It’s also an easy method to employ.  Once the lacquer thinner has worked through the system, you should experience improved performance, and hopefully, the rattling is gone as well.

2. You are using High Octane Fuel and Fuel Additives. It takes to clean out your converter to run higher quality gas through your system. If you usually use the lowest octane gas available, try running a few tanks of high-octane gas through your vehicle. It may be enough to increase airflow and stop rattling noises. Similarly, certain additives can be purchased that will help clean out your cat when they’re added to your gas tank.

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Catalytic converter making noise is not something usual in the car that you need to find a good way of fixing the issue. The article provides ways to reduce the noises in the converter and the signs of a bad converter.

Therefore, consider correcting the problems with the ticking noise in the car before they cause more significant damage to you. Always follow the manufacturer’s instructions before trying out anything. Choose to consult a technician in the troubleshooting process to help you work with the engine since it needs professional handling.

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