NEW VOICES: cat burglars

FrazzledJen-Luc2 [Note: Since I'm still feverishly working on Da Book and matching up science and Hollywood, I bring you another installment from my Santa Fe Science Writing Workshop student Alex Morgan. He mentioned the story of how his wife's catalytic converter was stolen, and why — I'd never heard of such a thing and encouraged to write it up as a blog post. And he did! How awesome is Alex?]

A few months ago, my wife, Janice, took her mother to the doctor. When the appointment was over, they came out. “I went to start the car,” she told me, “and there was this ROARING sound. I nearly wet my pants. It was incredibly loud. At first I thought the car was about the explode. Then I realized that something was wrong with the muffler. The car was running okay, but it was really loud.”

The next morning we took her car to a nearby auto shop, expecting that the muffler had somehow come loose. The car is only three years old, but you never know. The tech told us something we weren’t expecting. “Your catalytic converter’s been stolen,” he said. “They cut it off with this electric saw, takes just a minute, get $50 for it.” Then he told us it would cost $400 to fix, unless we wanted authorized GM replacement parts, in which case it would cost $800. Damn! 

A catalytic converter (“cat” from now on) is a bit of clever technology to reduce auto emissions. It looks something like a muffler and fits on the exhaust pipe between the engine and the muffler, which is why Janice’s car was roaring after her cat was stolen.  The exhaust of gasoline engines contains three nasty gases the cat is designed to eliminate: carbon monoxide, a deadly poison; oxides of nitrogen, that make smog and acid rain and can eat at your nose and throat and lungs; and hydrocarbons (mostly unburned fuel) that generate ozone and therefore smog.

The reason why cat’s are stolen and can be fenced for $50, whereas nobody is going to run away with your muffler, is a cat uses metals more valuable than gold: platinum, rhodium, and palladium. In a typical cat they are worth about $200, if legally obtained. These metals (the catalysts) help the cat split the oxides of nitrogen into harmless nitrogen and oxygen, and they also help burn up the carbon monoxide and hydrocarbons. One colorful description of the reduction of the oxides of nitrogen says, “the catalyst rips the nitrogen atom out of the [oxide] molecule and holds on to it, freeing the oxygen … “ Cats don’t reduce the greenhouse gas, carbon dioxide. They were mandated by the clean air act of 1970 and required on cars by 1975. People weren’t much concerned about global warming in the 1970’s. Catalytic-converter-location

But cats do help to clean up the urban atmosphere. Once a year, we in Detroit are privileged to participate in a spontaneous demonstration of this. On a designated Saturday in mid-August Janice and I take the kids to “The Woodward Dream Cruise,” in which people drive their lovingly restored vintage cars up and down Detroit’s famous Woodward Avenue.

Thousands of spectators in lawn chairs watch from the sidelines all day into the evening. Visitors fly in from across the world for the rare opportunity to see – all on one day and in perfect operating condition – the “land yachts” from the 1950’s, the gangster-movie cars of the 1920’s, the luxurious chauffeur-ready models of the 1930’s, the curvy streamlined cars of the 1940’s, Model T Fords and others of that era, along with some sixties favorites like Mustangs and Corvettes.

As much as we love the festival spirit and the sheer audacity of these exuberant machines, we have always carried away one negative reaction: It stinks. Pre-1970’s cars pass their unprocessed exhaust out their sometimes lovingly chromed exhaust pipes, and the smell along Woodward at the height of the Dream Cruse is nasty. (At least they don’t put lead in the gasoline anymore, but that’s another story.)

A catalytic converter for a car is like a diaper for a horse. Both converters and horse diapers make their respective transportation devices less likely to dirty the environment, but they add cost and complexity. (Yes, there are diapers for horses, required in some municipalities, for example, Charleston, South Carolina.)

It’s amazing how complicated cats have forced cars to become. The cat itself is a pretty sophisticated (and expensive) piece of technology, but the supporting technologies include oxygen sensors, computer-controlled fuel injectors, temperature sensors, and other fancy gadgets. My first car was a green 1965 VW beetle, still my favorite car of all time. It didn’t have a catalytic converter. In fact, it had no computer, no fuel injectors, no sensors, no platinum, palladium, or rhodium. I loved its simplicity. Of course, it also stank. More politely, it “didn’t meet emissions standards” and couldn’t be sold in the U.S. after 1975. By the way, vintage cars are exempted from emissions regulations, so the Woodward dream cruisers are legal.

Computer-controlled catalytic converters symbolize for me the technical changes required of the auto industry over the last thirty years. Cars have morphed from simple mechanical machines (like my VW) to electronic-mechanical entities enormously more sophisticated and delicate to design, manufacture, and maintain. They are controlled by a network of up to 50 computers and up to 40 sensors. The “grease monkey” repairman has morphed along with the cars into a computer technician. I’ve been told that 85% of repairs for cars now involve the electronic components, not just the mechanical parts. Cars being more technically complex than they used to be means that, when all is well, they do some pretty nice tricks. Of course, they also have many new ways to screw up.

Consider the converter. The following things can go wrong: it can be stolen, the oxygen sensor can fail, the catalytic metals can become poisoned (some fuel additives will do this), the converter can become clogged or it can start a fire. These last two may happen if the engine is not running properly and, say, an unusual amount of unburned fuel is being passed into the exhaust.

People are getting more and more worried about global warming and the cost of petroleum, so many new fuels (ethanol and various biofuels, hydrogen fuel cells) are being considered. We have to expect that the production and use of each of these new fuels will generate wastes and emissions that will need to be controlled. Replace your horse with a llama, and you’ve still got to fit the diaper and deal with what fills it.

Janice continued to be upset weeks after we got her car repaired. “It’s just really annoying and it really does seem petty that someone would put me through all that trouble to put $50 in their pocket. The shock of the noise was probably the worse part of it. I don’t drive clunkers anymore, and I’m not expecting the car to fall apart on me.” I considered lecturing her about how, as cars get more sophisticated and as new technologies are introduced, she’ll have to expect them to mess up in many new and unexpected ways. But I held my tongue. 

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