Top 7 Signs Of Stolen Catalytic Converter

A catalytic converter is an essential piece of your car. As you probably already know, this critical piece is located in your car’s internal combustion engine, and it serves to purify the toxic fumes being emitted into the air.

Due to its value – mostly linked to the highly precious metals used in its makeup – thieves are always targeting this little device. But how would you know if yours has been stolen? Below are some tell-tale signs.

Headache When Windows are Rolled Down

Are you having unusual headaches whenever your car’s windows are rolled down? Perhaps, that is a sign that you have a faulty exhaust system. Here’s the reasoning.

As alluded to earlier, the catalytic converter in your car serves to reduce the emission of toxic gases and fumes by catalyzing them in a redox reaction. If it goes missing, that means poisonous gases like carbon monoxide will be free to escape.

This carbon monoxide may be responsible for the headaches you are experiencing.

Loud Noise

That is the first and most obvious red flag that should inform you of the possibility of a missing catalytic converter. By loud noise, I mean that your car will suddenly start producing a loud and irritating noise whenever it’s in use.

If this happens to you, you will probably want to take an extra step and check whether the converter is still in place.

Check Engine Light Turns On

All cars come with engine control units whose function is to monitor sensors in your car’s engine bay. After a complete drive cycle, it will likely detect whenever your catalytic converter goes missing. That is because stealing the converter will trigger a faulty code.

Once the engine control unit detects this error, it will turn on your car’s check engine light.

It will not be possible to completely turn it back off unless you replace the stolen converter – even if you turn it off, the control unit will detect that the converter is missing after one entire drive and turn on the light again.

Reduced Low-End Torque

About your car’s combustion engine, torque refers to the amount of force the drive shaft is subjected. When torque interacts with the engine’s speed, it determines your car’s engine power.

Low-end torque is thus the sum of torque available at the lower engine rpm band. When the catalytic converter is stolen, the low-end torque reduces. As a result, your car becomes slower and less responsive, reducing your driving experience.

If you are an above-average driver, you will most likely notice when your car’s low-end torque becomes less. You should immediately check for the catalytic converter.

You Drive one of High Target Vehicles

While no vehicle is outside the ambit of thieves, high-target cars are more likely to have their converters stolen than regular vehicles. That is because, as economists might say, every individual acts in their own best interests to maximize profits.

Thieves, too, are looking for vehicles with large and easily accessible converters or two converters. Such cars include Toyota Priuses, delivery vehicles, and trucks.

While trucks and delivery vehicles have large converters and easy access, a Toyota Prius usually has two catalytic converters.

Missing Components Under Your Vehicle

Besides the loud irritating noise your car produces, the other most obvious way to tell whether your car’s catalytic converter has been stolen is by visual inspection. You have to get on your knees and check the condition of the components found under your vehicle.

If the converter has been stolen, then it was cut off, and that will be evident by looking at the other components – they will also have been cut. It will be essential to focus on the region above the exhaust manifold and the y-pipe.

It would be for the best if you took that chance to install a bumper protector.

What To Do If Catalytic Converter is Stolen

Contact the Police

The first thing you should do is contact the police. This will help create a paper trail in case the thief tries to sell the converter. Tell them what happened and when, and see if they can help you track down the culprit. If you have any surveillance footage of the theft, be sure to give that to the police as well. They may be able to use it to identify the thief and get your property back.

You can also post a reward for the return of the converter on websites or social media platforms

Next, check with your local scrap yards to see if anyone is trying to sell a catalytic converter that matches your description. If so, get the name and contact information of the seller and pass it on to the police.

Claim with the insurance

You should also file a claim with your insurance company. Many insurance policies cover the cost of repairing or replacing a stolen catalytic converter.

If your insurance covers stolen catalytic converters, you will need to pay your deductible, and the insurance company will pay the remainder of the repair costs.

Visit a Mechanic

Finally, you have to take your car for servicing. The mechanic will restore your vehicle to shape, and you won’t have to drive around with a missing converter.

How to Prevent Catalytic Converter Theft

State Farm, the world’s largest insurer, reports it processed 3 times as many cat converter theft cases in 2021 as in 2020 and more than ten times as compared to 2019.

Catalytic converter theft is a growing problem in the United States. The National Insurance Crime Bureau (NICB) reported nearly 11,000 catalytic converter thefts in 2019, a 36% increase from the previous year.

According to Colby Sandman, the owner of Muffler Tech, the replacement cost for a Toyota Prius cat converter costs as much as $3,000. And in recent times, his shop replaces 15-20 cat converters due to increasing theft cases.

Cat’s contain precious metals like palladium, platinum, and rhodium that can be sold for a high price. Second, they’re easy to remove since they’re usually located under the car.

Invest in an Anti-Theft Device

Investing in a cable locking mechanism is far less expensive than replacing a converter. The Online world is filled with protection devices for the cat, which is part of your vehicle’s exhaust system and runs along the undercarriage—these anti-theft devices range from $250 to $800.

Here are some of the most common devices:

  • A shield made of steel covers the catalytic converter & requires additional time and equipment to remove.
  • Cages built of rebar or other difficult-to-cut high-strength steel.
  • Welded stainless steel wires connecting the converter to the frame of the vehicle.
  • Some exhaust shops will custom-weld this device to your vehicle. However, mounting the catalytic converter directly to the vehicle’s chassis might make the car loud, as the exhaust system is often hung from the vehicle by sound-dampening hangers.

Park in a well-lit area

Park in a well-lit area, especially at night. This will make it more difficult for thieves to target your vehicle.

Consider installing a security system

Many cars nowadays come equipped with a security system, but if yours doesn’t, you may want to consider installing one. This will help deter thieves, as they will know that it will be more difficult to steal your catalytic converter if an alarm system is in place.

Engrave your catalytic converter

One way to make your catalytic converter less attractive to thieves is to engrave your name or license plate number onto it. This way, it will be easier to identify and recover if stolen.

Keep your car in a garage

If you have the option, keeping your car in a garage is an excellent way to protect it from theft. This will make it more difficult for thieves to access your vehicle and remove the catalytic converter.

Don’t leave your car unattended for long periods

Avoid leaving your car unattended for long periods, especially in public places. If you must leave your car somewhere, ensure it is in a well-lit and busy area. The longer your vehicle is left alone, the more likely someone will try to steal the catalytic converter.

Can You Tell If Your Catalytic Converter Has Been Stolen?

Yes, you will. However, that is not something you will notice out rightly by just looking at your car. It will come to your attention once you start the car since it will produce a loud and irritating noise.

-Further, you can tell whether it has been stolen by looking at the car’s check engine light that the engine’s control unit will have turned on after a complete drive cycle. You can also do a visual examination under your car, where you will notice that some components have been cut off.

Does Insurance Cover If Someone Steals Your Catalytic Converter?

Catalytic converter theft is typically covered if your motor insurance policy includes comprehensive coverage. The comprehensive coverage may cover the cost of replacing the converter and repairing any damage caused by its theft.

Nevertheless, it is necessary to confirm with your present insurance agent that you are covered in the case of such a theft. It’s important to note that comprehensive insurance doesn’t cover everything, despite its name.


Catalytic converter theft is a common occurrence. More cases are recorded when the worth of the catalytic converter is higher. Thus, some vehicles will be at a higher risk than others. High-risk vehicles include trucks, delivery vehicles, and Toyota Priuses, with larger converters or two converters. If you become a victim, be sure to report to the nearest police station for investigations to commence.


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