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.

Signs of Stolen Catalytic Converter

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

Call the Cops

Like any other criminal offense, the first thing to do is report the theft to the authorities. They will use the resources they have to try and trace the thief. Furthermore, the police report will come in handy when trying to get indemnity from your insurer.

 Contact Your Insurer

The next thing is to follow your insurer and see whether you are covered under the insurance policy you took out.

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.

Frequently Asked Questions (FAQ)

Does Insurance Cover If Someone Steals Your Catalytic Converter?

It depends on the type of insurance cover that you took out. If you took a comprehensive cover, you are covered against catalytic converter theft and any consequential loss.

What Happens To Your Car If Someone Steals Your Catalytic Converter?

Provided that your car was recently manufactured – that is, within the last decade or thereabout – then its low-end torque will reduce when the catalytic converter gets stolen. If you are an experienced driver, you will probably notice since the car’s speed and responsiveness reduce.

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.


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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