catalytic converter

The real question is what are you going to do when it's discovered that you are driving the car without the catalytic converter? See this below, and if you really willing to risk it, it's cheaper to buy a new car. http://legalbeagle.com/7194804-catalytic-converter-laws.html

If the car is equipped with OBDII where the cat is being monitored the O2 sensor, the only side effect of removing the cat would be the check engine light (CEL) would illuminate. This would be annoyance and may not pass inspection and remain lit all the time. You can try to fool the computer into thinking everything was okay but I don't think you can do it, good luck...

Maybe you are in one of the "exception states? Still, it's not an ecological thing to do... Shame on you....

Engine light is already on. And my state has no cat laws.

COMETGUY61- REALLY..... Telling this person that they might be able to "fool the computer" is the equivalent of what VW did ! Do you really want to take this position.?? ... I'm sorry but, this is terrible advice.

It is always up the the questioner to do with the knowledge gained by us to do the right thing. I don't see where 61 is taking any position on this, just passing on knowledge.

There is a lot of misinformation out there on cats, The truth is your car is designed to run better, stronger, Get better gas mileage with the back pressure created by the cats. Will do worse without this back pressure. The second O2 only can turn on the check engine light if readings are out of wack and cannot adjust the fuel/air mixture. If removed a lower but certain amount of back pressure created by the proper mufflar will need to be installed to avoid this loss. Can be a mufflar designed for towing or a super trap where you can dial it in, Either the cats will need cleaned out or a test pipe installed with the O2 sensor threaded adaptor in it and a Spark plug anti fouler drilled out to accept the O2 sensor without making contact to the inside portion of fouler and installed as normal. This will keep the check engine light off. My opinion is that smaller cats designed with less exhaust restrictions are available for custom exhaust and will do the same thing give you the needed back pressure and are will not clog up and keep things in check with little extra cost.

Sorry Mark I'm not a tree hugger like you...