So I picked up my IS 250 a years ago and now my gas mileage has dropped horribly, loss of power with the car going into limp mode if I mash the throttle with a nice sulfur smell to annoy the folks behind me. I have a P0430 and pending P0420 So Im gonna assume my Cats are pretty much clogged up. I cant afford new Cats and Labor cost so I was told that I can just drill a hole in the Cats to get it to run better although the O2 sensors will still throw a code. So has anyone else been able to fool the ECU by using the " Non Fouler" Trick?