It’s the kind of theft you don’t realize until the second you start your car.

What was once a relatively quiet engine startup is suddenly a loud, booming sound – almost like a hot rod.

Catalytic converters, a critical automobile part to reduce emissions, are being increasingly stolen across California and the country, stripped and sold for the precious metals they are made of – partly because they’re easy to remove.

“​​This is a huge, huge problem,” said Lt. Mario Martinez, a spokesman for the Garden Grove Police Department, in a phone interview last week.

He said there have been 166 catalytic converters stolen in Garden Grove between January and the end of March this year alone – adding that it’s a problem that extends beyond the city.

“I was just talking to detectives, they’re obviously overwhelmed and overworked. They have made one arrest, but they’re hoping to have several more. They’re currently working on some active cases involving catalytic converters.”

The increasing thefts are leading officials across Orange County in cities like Irvine and Lake Forest to pass ordinances in an effort to provide a tool to police officers to try and crack down on those thefts where they say state laws fall short.

Huntington Beach is one of the most recent cities in the county where officials have moved forward with an ordinance prohibiting the unlawful possession of catalytic converters.

City council members there voted unanimously to introduce the ordinance at their meeting earlier this month. 

“This is on, I think, the police reports everyday, it’s outrageous,” said Mayor Barbara Delglieze at the meeting. “The state is also working on ordinances so it’s only going to get better for, I think, the car or truck owner.”

In 2019, there were 49 catalytic converter thefts reported to the Huntington Beach Police Department. In 2020, that number climbed to 192 thefts and jumped to 461 in 2021, according to city staff.

What is a Catalytic Converter?

A catalytic converter changes the harmful emissions like gasses and pollutants from a car’s exhaust into less toxic pollutants. It looks like a small metal box and is located under the car, according to the Universal Technical Institute, which trains automotive technicians.

“This was implemented by the (U.S. Environmental Protection Agency) in 1974 to protect the environment and are necessary to pass the state vehicle inspections,” said Huntington Beach Assistant City Manager Travis Hopkins at last week’s meeting

Catalytic converters are made out of precious metals like platinum, rhodium and palladium,  making them targets for thieves who can sell the converters to scrap metal yards. 

Replacing a catalytic converter can cost about $2,000 to replace, according to the institute.

It’s also easy money for criminals who can get anywhere from $200-$1200 per converter from metal scrap yards, according to law enforcement officials in Irvine and Mission Viejo. 

The Universal Technical Institute recommends parking in well-lit places or a secure garage to prevent catalytic converter theft.

They also recommend welding the catalytic converter to the vehicle frame as well as engraving your vehicle identification number on the catalytic converter to make it harder to steal.

Local police departments are also recommending car owners etch identifying information on their catalytic converters.

Costa Mesa Police, along with Huntington and Newport Beach police departments, hosted a free event in partnership with ExperTec Automotive where 130 vehicle owners got their catalytic converters etched.

“By etching catalytic converters with vehicle identifying information we hope to deter theft. It will also assist law enforcement to identify the victim and return the stolen property,” reads an email from Roxi Fyad, a spokesperson from the Costa Mesa Police Department.

To read more about the catalytic converter and tips on how to protect it from being stolen from your car click here.

One of the biggest hurdles in prosecuting stolen converters is that there isn’t any state law regulating their possession, according to multiple ordinances passed by cities like Irvine and Huntington Beach, unless it’s proven stolen.

They’re also relatively easy to steal from under the car, police say.

“A lot of the crooks, they take these portable saws, they cut it, they’re in and out within seconds, and they don’t leave any evidence behind,” Martinez said.

While some cities have encouraged residents to get their license plate numbers inscribed on the converters so they can prosecute the thieves if the item is recovered, most are going another route. 

What Do The Laws Do? 

The ordinance in Huntington Beach would make it illegal for anyone, except a core recycler to possess any catalytic converter not attached to a vehicle without valid proof ownership.

Unlawful possession of a catalytic converter could result in a misdemeanor punishable by a fine of up to $1,000 or six months in jail or both.

“The ordinance would provide the Huntington Beach police department with the legal authority to deter and potentially reduce the transfer and theft of catalytic converters that are stolen locally,” Hopkins said.

At the same meeting, Councilman Mike Posey asked why not make unlawful possession of a catalytic converter a felony if it costs so much to replace.

“Misdemeanors mean virtually nothing,” he said. “If the penalty is not sufficient to deter, maybe we should be looking at other charges that can amplify the penalties and vigorously prosecute every single one.”

Huntington Beach’s effort came after Mission Viejo Council Members unanimously introduced their own ordinance to deter catalytic converter thefts last month.

Captain Quyen Vuong with the Orange County Sheriff Department told council members at that meeting that without an ordinance, law enforcement can not seize stolen catalytic converters.

“What’s enticing for the thieves is that there are no serial numbers, there is no (Vehicle Identification) number, there is no license plate number that’s attached so it makes it very challenging for law enforcement to find the lawful owner,” he said.

Vuong also provided statistics on catalytic converter thefts in Mission Viejo and neighboring cities.

In 2019, there were 11 reported catalytic converters thefts in Mission Viejo. In 2021, there were 182 in Mission Viejo, according to Vuong.

His data showed that the thefts were higher in Irvine, with 535 thefts in 2021 reported to law enforcement.

Irvine City Council Members approved a similar ordinance in October 2021, saying that 99% of the city’s catalytic converter thefts had gone entirely unsolved. 

A Different Route

In January, Costa Mesa launched an ongoing catalytic converter bait program to prevent these types of thefts by putting up signs on thoroughfares entering Costa Mesa as well as posting about it in social media.

“The police department parked several different bait cars throughout Costa Mesa neighborhoods and officers are working in an undercover capacity to catch thieves in the act,” reads the email from Fyad.

She said in 2020, there were 115 catalytic converter thefts in Costa Mesa in 2021 there were 318

Garden Grove Police Lt. Martinez said the theft of catalytic converters is already considered a felony in his city because of their value.

When asked about if the ordinances passed in other cities like Huntington Beach would be helpful, Martinez said it would take time to research how effective they actually are.

“Any help would be useful for us but obviously, there would have to be some research that goes into it. Are the DA offices going to be filing charges on those kinds of city ordinance?” He said. “We’ll see how successful Huntington Beach and other cities are and that might be something that thinking out of the box that we could do.”

In an email to Voice of OC, Anaheim Police spokesman Sgt. Shane Carringer said the city hasn’t approved any laws beyond what exist at the state level, but that officers work to connect converters with ones reported stolen in recent days. 

“I’ve been a cop in Anaheim for 20 years, they’re nothing new but they’ve boomed recently,” Carringer said. “There may be ways to assume the property that was stolen was from them, but they aren’t serialized to those vehicles.” 

But a new state senate bill could change that. 

Sen. Tom Umberg, whose district covers parts of Anaheim, Santa Ana and Garden Grove,  proposed a bill titled Senate Bill 986 that would require car dealers to apply a vehicle identification number to catalytic converters the same way they do with other car parts, like the engine block and transmission to make it easier to track where the part came from. 

The law would also require recyclers to record the unique identification number of each converter they recycle, meaning they’ll be able to trace where the parts ended up at. 

The law has already been endorsed by both the LA and Orange County Sheriff’s Departments, along with the cities of Huntington Beach, Lakewood and Buena Park. 

Hosam Elattar is a Voice of OC Reporting Fellow. Contact him at or on Twitter @ElattarHosam.

Noah Biesiada is a Voice of OC Reporting Fellow. Contact him at or on Twitter @NBiesiada.

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