Catalytic converter locks and alarms: Do they work?

A pile of stolen catalytic converters are shown.
Utah Attorney General's Office via AP

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Thieves are increasingly targeting catalytic converters on cars. If yours is stolen, replacing it could cost you thousands of dollars.

So are inexpensive alarms, locks and plates a solution to keep the crooks away from your car? Lisa McNee would love to know: she is now among the thousands of catalytic converter theft victims in the past year.

“The car was parked there, right in front of the house,” she said when her converter was recently stolen.

She provided us doorbell cam video, which showed a shadowy figure pulling up to her car at night, leaving her with over a $1,000 repair bill. Thieves steal catalytic converters, hoping for a big payday by melting down the precious metals inside.

CARFAX reports that as many as 153,000 were stolen in the year 2022.

Devices That Might Prevent Theft

So what can you do? Several devices claim they help you deter a thief.

For about $200- $300, you can have a shop install a metal plate over your converter, making it very tough to steal.

But many drivers don’t want to pay that much, but you can find some cheaper options on Amazon. You can purchase catalytic converter locking cables for around $150. Or you can buy a simple motion sensor alarm for just $30.

We Test One Out

We ordered a $29 alarm and took it to Duebber’s Auto Repair, where Marc Duebber agreed to install it.

He looked over the device, which you strap onto your car’s exhaust pipe with a small heat shield to keep it from melting. He put batteries in the alarm and remote control, then put our Ford Escape on a lift and strapped on the alarm.

After setting the alarm with the provided remote, he tapped the tailpipe to test it out. It worked. On the third light tap, a loud alarm could be heard throughout the repair shop.

Duebber, however, wonders if it’s enough to scare away a thief.

“A determined thief,” he said,” would probably keep cutting and take the converter anyway.”

But he admits a casual thief might run the moment the alarm went off.

MORE: The Best Car Electronics and Accessories

Other Things You Can Do, According to CARFAX:

  • Park in a well-lit area
  • Install motion sensor security lights outside your home to deter thieves
  • Ask a shop to etch your car’s VIN on the converter

“The VIN etching is great for police once they find a thief, but it doesn’t often stop a thief,” CARFAX’s editor-in-chief Patrick Olsen said.
For McNee, any of these protective devices is better than nothing.

“It’s terrible people are out there doing this,” she said.

So consider extra lighting, a protective lock or a simple alarm, and that way you don’t waste your money.

About the Author

John Matarese

John's goal is to help as many TV viewers as possible save money, avoid bad deals, know a rip-off when one comes their way, and be educated consumers. His informative weekly consumer segment "Don't Waste Your Money" now airs on 45 TV stations from San Diego to Tampa to Houston and Cincinnati. More.

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