Energy cannot be created or destroyed - true. But energy can be coverted into some other form (like an electric motor that converts electric energy to mechanical energy). The catalytic "converter" does not store polluting emissions - it "converts" them to non harmful or inert substances that can be safely decomposed. It is ludicrous to even think that a catalytic converter stores up all the emissions and releases it all when junked.mx3gtracer wrote: I have a phrase to call upon: you can not create nor destroy matter. In other words while the cat keeps some pollutants from coming out the tail pipe, keep in mind that doesn't mean they don't exist, when the car dies or the cat is pulled, it goes to a scrap yard or a dump and guess where those pollutants are going to be, released... in the end the pollution angle results in an argument of when the pollution will be released.
For catalytic converter basics - http://auto.howstuffworks.com/catalytic-converter.htm