Catalytic Converter Theft Spikes in Colorado

Over the past couple years, Denver has seen a large uptick in the amount of catalytic converter (“cat”) thefts. Denver PD reported a 1,613% increase in cat theft between 2019 and 2020. The growth trend has continued strongly through 2021. It leads us to wonder, why there is so many thefts, and why would somebody want to steal my catalytic converter? Many other cities across the nation such as Dallas, Honolulu, Missoula, Montana, Orlando, Rochester, and San Francisco are similarly reporting a large spike in vehicle and catalytic converter thefts. Oceanside Police Department in California has predicted catalytic converter thefts to rise up to 30% in the next two years. Many experts are attributing these crimes to the pandemic. With the loss of community and youth outreach programs, many at-risk youths have resorted to criminal activity. Moreover, the economic downturn, loss of jobs, and cuts to law enforcement budgets since the start of the pandemic have further flamed vehicle theft and crime.

Stolen catalytic converters recovered.Reports suggest that the increase in theft could be attributed to supply chain issues. Colorado, among other states, switched to CARB (California Air Resources Board) compliant emissions standards effectively January 1, 2021. In effect, the change in law created a higher value for the black market to sell catalytic converters, not to mention the intrinsic high value of rare earth metals (platinum, palladium and rhodium) in those cats. Of course, this does not mean switching to a CARB compliant state is bad; the standard is designed to increase our air quality and improve the life cycle of cat repairs relative to the EPA compliant catalytic converters. In the long run, the standard allows residents to breath cleaner air while allowing drivers to avoid multiple catalytic converter repairs due to a higher upfront standard. A common misconception with becoming a CARB compliant state is that we can only source parts directly from the vehicle manufacturer, however there are several companies that do comply with carb compliance regulations such as Walker Exhaust, Magna-flow and AP Exhaust. 

What is a Catalytic Converter?

Catalytic converters were invented in the earlier 1970’s and became a required component in 1975 to improve air quality. In chemistry a catalyst is a chemical that expedites a reaction without changing the process or results of that reaction, and in catalytic converters the catalyst is a combination of several precious metals such as palladium, platinum, and rhodium. Inside a catalytic converter is a honeycomb like structure made from ceramic and coated in catalysts that is partnered with heat in excess of 600°F to create the chemical reaction of breaking down the harmful fumes such as carbon monoxide and VOC’s (volatile organic compound) into less harmful fumes like carbon dioxide and water vapor. Unlike what you may predict, a catalytic converter does not act a as a filter but instead rearranges the atoms, so it will take nitrogen oxides (NOx) and turn it into nitrogen and oxygen.

Most vehicles are also equipped with a “pre-cat” that is a very small catalytic converter that sits very close to engine so that it may steal some of the heat coming out of the engine to neutralize the exhaust fumes until the main catalytic converter can get up to optimal temperature. You shouldn’t worry about the pre-cat getting stolen due to its low scrap value and how close it sits to the engine making it very inaccessible.

Why are Catalytic Converters Being Stolen?

The scrap value of a catalytic converter can range anywhere from a few dollars for a “pre-cat” to several hundred dollars for some of the larger catalytic converters and especially hybrid-vehicle catalytic converters. The rare earth metals are particularly valuable due to their scarcity value. Hybrid vehicles are one of the largest targets for catalytic converter theft because they use a combination of gas and electric motors, therefore having a lower amount of contamination by producing less exhaust. We assume the quality of these catalytic converters are better as there is less strain on the units, relative to other non-hybrid vehicles. Hybrid catalytic converters are also typically only supplied from the original vehicle manufacturer with little to no aftermarket replacement options. This means there is more of those precious metals inside that raises the scrap value. Some aftermarket companies do produce high quality cats but it is less consistent than the original manufacturers. 

Also, catalytic converters are easy to steal based on their placement under the vehicle. They typically only take seconds to minutes to seize with a Sawzall and cut out from the exhaust. SUV’s and higher clearance vehicles are more targeted because of how easy it is to crawl underneath without a jack. Honda Elements, in particular, have been victims of this trend. Considering cats traditionally do not have identification number, it is less traceable than perhaps a gun.  This makes catalytic converter theft a lower risk crime.

How Do I Know if my Cats were Stolen?

Stolen catalytic convertersYou likely won’t be able to see any signs of vandalism prior to starting your car but after initiating the ignition, the circumstance becomes clear. The subsequent noise will be startling, and the sounds has been described as boat or a lawn mower engine. This is because the catalytic converter sits before the muffler, a part partially designed to dampen noise, in the exhaust system. If you notice that sound or are suspicious that your catalytic converter might have been stolen you can peer underneath your vehicle and look for a hole in the exhaust system, typically more centered in the vehicle.


Preventive Measures

  • Park your vehicle in a locked garage. Although this is the most effective theft deterrent, plenty of Coloradans lack this luxury.
  • Find a parking spot in a well-lit area in public view.
  • Install anti-theft devices such as a cat-clamp or cat-shield that are designed to encapsulate the catalytic converter in a manner that is difficult and more time consuming to cut through. It would require enough additional steps that the thief would rather move on to the next target. Many automotive shops including Hotchkiss Auto Repair can install those prevention cages at a fraction of the cost of a catalytic converter replacement.



Avoid leaving a vehicle parked in the same spot for an extended period. Many thieves will target these vehicles because they know the stolen cats will not be discovered for a long period and at that point the potential trail to them has gotten cold.


If you do run into the unfortunate situation of having your catalytic converter stolen, it is best to immediately contact a highly reputable independent repair shop like Hotchkiss Auto Repair. The shop should be able to advise you on the need for towing, reliability to drive the vehicle, and repair options.  In addition to the catalytic converters, often times oxygen sensors are also stolen or damaged in the process of cat theft. Depending on the nature of the theft, a repair can be a thousand bucks to several thousand dollars. In this situation, it is helpful to have comprehensive insurance as most insurance companies will cover catalytic converter theft.

The team at Hotchkiss Auto Repair has been serving Denver metro residents across three decades.  We have numerous awards for being among the best shops in Denver; give us an opportunity to serve you and your family!  Whether it is a catalytic converter replacement, an oil change, or a periodic tune up, we’re your trusted mechanics for all general automotive needs.  Call us to discuss any vehicle concerns or schedule an appointment ASAP.  Our team can be reached at 303-780-7747.  Thanks!



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What's the difference Between CARB and EPA Catalytic Converters? . Walker Exhaust Systems | Performance Mufflers & Exhaust Kits. (n.d.).

Denver sees 1,600% spike in catalytic-converter thefts during pandemic, Denver Post by Laura Studley, 18 Feb 2021,