How to Tell if a Catalytic Converter is Clogged

How to Tell if a Catalytic Converter is Clogged – An effective and efficient functioning of a car depends on certain critical components and the catalytic converter is one of them. 

A catalytic converter in a vehicle is an emission control device that is found within the exhaust system. Its job is to take toxic gases including pollutants in exhaust gas from the internal combustion engine and convert them to less-toxic pollutants.

The toxic gases here include unburned hydrocarbons, nitrous oxides, and carbon monoxide. 

What happens within the exhaust system is that the catalytic converter turns the unburned hydrocarbons into water and carbon dioxide. It turns carbon monoxide into carbon dioxide, and also turns nitrous oxides into nitrogen and carbon dioxide.

Why do people steal catalytic converters?

Stealing of the catalytic converter has been common in recent times. But the question is, why do people steal catalytic converters?

The only reason that you see people sawing off or stealing the catalytic converter is as a result of some precious metals that are in there. 

The catalytic converter in itself helps clean out toxic gases and makes them less toxic as they enter the atmosphere.

Every vehicle must have a functioning catalytic converter to pass the safety and emission test.

Rhodium, one of the most valuable metals can be found in the catalytic converter and it’s the single reason thieves are always going after the catalytic converter. 

Other precious metals found in the catalytic converter include Palladium and Platinum. 

These precious metals in combination with the ceramic-coded beads serve as the catalysts that convert poisonous gasses such as carbon monoxide, nitrous oxide, and hydrocarbons to less-harmful gasses such as carbon dioxide, nitrogen oxide, and water.

One of the most targeted cars for thieves looking for the catalytic converter is the Toyota Prius. 

The Toyota Prius is well known for its low emissions because of the enormous amount of Rhodium, Platinum and Palladium contained in its catalytic converter.

The Toyota Prius is just one of the low-emission cars. There are more but the point here is that catalytic converter thieves usually target low-emission vehicles.

Catalytic converter theft is also common among SUVs and certain trucks because they have high ground clearance. As such, one can easily get under the vehicle and remove the unit. 

Vehicles with catalytic converters welded on them also have a high risk of having their catalytic converters removed using pipe cutters.

How much is the worth of a stolen catalytic converter? 

In the scrap market, a stolen catalytic converter can be sold for between $400 – $700. 

How to tell if a catalytic converter is clogged
Toyota Prius Hybrid 2010 with a stolen catalytic converter

Can I drive without a catalytic converter?

You may be wondering, “Can I drive without my catalytic converter?” Well, the short is yes. 

Considering the function of the catalytic converter, you can still drive your car without it. The engine won’t get knocked if it’s not there.

However, you’ll be unfair to yourself and every other person out there if you choose to drive without the catalytic converter device.

The function of the catalytic converter is basically to help every one of us avoid lung problems as a result of inhaling toxic gases that may have been released from our car into the atmosphere.

So, if you and every other person choose to drive without it, imagine the harm that we’ll all do to ourselves. 

While the short answer of whether you can drive without a catalytic converter in your car is yes, the long and perfect answer is no, considering the fact that you will be putting your life and those of others in danger.

Apart from the above, you’d be exposing your car to more problems as a result of the exhaust system not functioning well.

What is the cost of a catalytic converter repair?

The cost of a catalytic converter repair can be as high as $2500. 

Nonetheless, if other parts of the engine were affected in the process of the thief removing the device, the cost could go up. Also, depending on when you attend to the problem, other problems may have arisen as a result of the catalytic converter going bad.

Note that this is just on average and it covers the cost of the actual part and labor. 

While you can get a fairly used catalytic converter between $1500 – $1700, you should go for the brand-new catalytic converter for two main reasons. 

One is that you need to be sure of what you are buying. Also, you may be discouraging the theft of the unit because you may not know if the used “cat” that you want to buy was stolen from another vehicle.

How can I prevent my catalytic converter from being stolen?

If you play your role, you can prevent thieves from stealing your catalytic converter. 

The tips here can be helpful. 

Install a protective device around your catalytic converter

Installing a protective device can prevent thieves from having it easy to cut off your catalytic converter.

Installing a protective device for your catalytic converter may cost you some money but at least it’s better than having to spend over $2000 – $3000 to replace it.

The protective device would also help you to avoid the discomfort that comes as a result of your catalytic converter being stolen.

Park your car in a safe place 

Bearing in mind that nowhere is safe, you have to be conscious about where you park your car to help prevent catalytic converter theft.

It’s better to park where there’s a security camera than where there’s none. This can help the authorities to hunt down the person that stole your catalytic converter or any other thing from your car. 

When driving home and if possible, always park your car in a garage and have the place locked.

When parking in public, do so in a place with high foot traffic. It’d be very difficult for anyone to try to saw off your catalytic converter in a place where people are constantly moving. 

Lastly, don’t park your car in the dark where thieves can operate without anyone seeing them. Always park your car in a well-lit area. 

Install an alarm system in your car

This can help as well. However, it shouldn’t be just an alarm but a vibration-triggered alarm. 

A vibration-triggered alarm is such that once there’s a vibration coming from any part of the car, it triggers the alarm to go off.

Luckily, newer vehicles now come with a vibration-triggered alarm with high-tech sensors that monitors vibration in any part of the car.

This should be the preventive measure that you should adopt to scare away catalytic converter thieves from your car.

How to tell if a catalytic converter is clogged or stolen

Apart from the reasons mentioned above not to drive a vehicle whose catalytic converter is clogged, damaged, or stolen, you are also going to experience certain signs signaling that all is not well with your catalytic converter.

The catalytic converter is one of the key components of any vehicle. As much as it works to keep your car sound, it can also impact our health, especially when it’s bad or removed and the car is still in use. 

They function to guard against the emission of toxic gasses that are detrimental to our health.

A clogged catalytic converter is one of the common catalytic converter problems. When it happens, it hurts your car’s performance and may lead to other problems for the engine if the problem if it doesn’t get the attention it requires promptly.

The tell-tale signs of a clogged catalytic converter are usually there and even if you may not be a car mechanic, you can still tell if your catalytic converter is clogged.

You can find your catalytic converter within your vehicle exhaust system. Precisely, it’s located between the exhaust manifold and muffler.

The catalytic converter can last for more than ten years because of the stable nature of metals used to create it. However, the catalytic converter can become clogged, overheated, contaminated, or physically damaged. 

Once the catalytic converter is bad, the car begins to throw up symptoms, which if not checked immediately can lead to the engine shutting down.

Common issues that could make your catalytic converter get clogged include driving with bad fuel or having engine misfires

As a result of these external issues, carbon begins to build up in your exhaust pipe, which eventually leads to your catalytic converter getting clogged.

A clogged catalytic converter is usually associated with the P0420 check engine error

Other times, you can tell if a catalytic converter is clogged if you observe the following symptoms at a glance.

  • Unstable engine RPM.
  • Dark exhaust smoke.
  • Poor acceleration.
  • Capped or limited speed.
  • Perceiving the smell of sulfur or rotten eggs from the exhaust.

These are usually some of the common signs to tell if a catalytic converter is clogged, but there’s more.

Additionally, two situations can lead to catalytic converter getting clogged, damaged, or bad. 

First, the materials making up the catalytic converter can break apart and render the device useless or the catalyst inside it can stop working because of aging.

Generally, the following are signs and symptoms of a clogged catalytic converter.

Your car makes loud noises

Your car is bound to make loud noises when driving, especially when matching the gas pedal.

The exhaust system is responsible for managing the noise that passes through the exhaust pipe of the car. 

It is common knowledge that the resultant effect of tampering with the exhaust system is a loud noise, be it in a vehicle or motorcycle.

A loud noise is also heard when starting a vehicle due to the absence of the catalytic converter.

Different engine problems

Engine problems such as unstable RPM, poor engine acceleration, difficulty starting, or capped/limited speed can signal a problem with your catalytic converter.

The problems listed above are a result of the engine being choked. The point is that the engine finds it difficult to push out the exhaust gases in a way that it should be hence resulting in creating more problems.

When the car cannot let go of the exhaust gases, it creates more heat for the engine and because of that, the car’s temperature may tilt a little above normal. The car is also seen finding it difficult to speed up.

High backpressure / O2 voltage

Using a car error scanner such as the OBD-II scanner can help you to tell if your catalytic converter is clogged. 

When using the OBD-II scanner, what you are primarily looking for is the high backpressure / O2 voltage signal. 

The reading on the device should hover between 0.5 – 0.7V without much fluctuation for a normal backpressure / O2 voltage reading.

Using an OBD-II scanner, a 5% fluctuation is the ideal value. A 10% fluctuation is good while a 30% fluctuation shows that your catalytic converter is clogged.

Ideally, you’d have to drive for like 10-15 minutes before connecting your OBD-II scanner to its port under the steering. Keep your focus on the live data while looking for the right O2 sensor that’s related to the catalytic converter.

As said earlier, your reading should fall between 0.5-0.7V which shows your catalytic converter is in perfect condition.

When using a normal backpressure gauge, the ideal value should be between 1 – 1.5 PSI. However, a reading of 1.6 – 2.5 PSI is just OK, while 2.6 – 3+ PSI means that the catalytic converter is clogged.

How to tell if a catalytic converter is clogged

Your vehicle is bound to fail the safety and emission test

One of the core checks carried out during a safety and emission test or inspection is the effective functioning of the exhaust system.

The exhaust system check is specifically about the present and effective functioning of the catalytic converter. 

Other things checked within the exhaust system include but are not limited to the exhaust pipe, muffler, EGR valve, pump system, oxygen sensor, and PCP valve.

During vehicle inspection, your car is also checked for the functioning and state of your vehicle’s headlights, tires, turn signals, brakes, brake lights and other accessory lighting, windshield wipers, windshield glass, rearview mirrors, horn, steering system, and window tints.

Once your car fails the annual safety and emission inspection, you won’t be able to renew your vehicle registration.

A damaged or clogged catalytic converter can never pass an emission test. You may choose to take your car in for an emission test where it’s done.

In New York, Massachusetts, Vermont, New Hampshire, and Georgia, it is compulsory for your car to pass an emission test before it’s certified to be on the road.

Harmful emissions

You have been using your car for quite some time and you know how the exhaust smoke used to be (color) including its smell.

Once your catalytic converter is stolen, this is bound to change. You’d begin to see your car smoking more than normal. The smoke color changes to dark.

At this point, your car can no longer convert harmful toxins such as unburned hydrocarbons, carbon monoxide, and nitrous oxide into less harmful emissions such as water and carbon dioxide.

The “check engine light” comes on

The “check engine light” can show up as a result of some other problems. Hence, you should be able to notice other symptoms before you can ascribe them to a problem with your catalytic converter.

The system can throw up the “check engine light” for engine misfires, which may be associated or could lead to a problem with your catalytic converter. 

Other times, a bad spark plug can cause a misfire.

Nevertheless, there is also the “check engine light” that associates with a problem with the catalytic converter being clogged.

Using the OBD-II to scan your car, you’d most likely get the P0420 error code, which means that the problem is associated with your catalytic converter.

The error code itself means “catalyst system efficiency below threshold in bank 1.”

Generally, the issues that could cause your car scanner to throw up the P0420 error code include:

  • Engine misfire.
  • Oil contamination in the catalytic converter.
  • Faulty catalytic converter.
  • High fuel pressure.
  • Damaged/leaking exhaust manifold.
  • Damaged/leaking muffler.
  • Damaged/leaking exhaust pipe.
  • Faulty front/rear oxygen sensor.

Hotter exhaust pipe than usual

You can easily check the temperature of your car’s exhaust pipe by using the infrared thermometer. If it appears hotter than usual, it’s an indication that your catalytic converter is clogged.

To tell if your catalytic converter is clogged by conducting a temperature test around your exhaust pipe:

  • Take the temperature measurement of the exhaust pipe.
  • Take the temperature measurement after the catalytic converter.

Usually, there ought not to be much temperature difference between these two points. Now, the big temperature difference between the temperature of the exhaust pipe and that of the catalytic converter shows that the catalytic converter is clogged or bad.

Note that your temperature measurement should be done when the car must have worked and raise the exhaust system to its operating temperature. A fifteen to twenty minutes drive is enough for this.

When do I need to change my catalytic converter?

The catalytic converter is built to last. Typically, it can take up to 10-15 years or even more before it begins to throw up symptoms that it’s bad.

But it should only be replaced when the need arises. In other words, it should be changed once it’s certified damaged after proper diagnosis and in consideration of several symptoms that it’s bad. 

How old the catalytic converter has been in the car shouldn’t be a factor when considering if it should be changed or not.

Certain factors contribute to the catalytic converter getting bad. The engine coolant should be protected from leaking into the combustion system. 

The coolant can easily clog the catalytic converter and once that happens, the exhaust gases can’t pass through. As such, the exhaust system shouldn’t be allowed to get blocked by anything as the car engine needs more air.

Other times, road debris can damage the catalytic converter.

Reply