SES/catalytic converter?
I have a '00 Z28 A4 with some bolt-ons, Y3000 stall, borla exhaust & lid. Lately I've been getting an "SES" light, and would reset it myself. This would last for about two months before it would pop up again. Now it seems as if I'm having to reset it every other day now. I finally sent it to a shop to be diagnosed, and according to their equipment it was signaling that my catalytic converter was the culprit.
Afterwards, I took the car to a local muffler shop, and was informed that if was my "cats" it probably was due to running "supreme" fuel which I've done religiously since day one.
What do you guys think about this? By the way my car now has over 113,000 miles on the odometer.

BTW: I just saw the amount of miles on your car. It's possible the O2 sensors are getting weak and the outputs between the front and rear sensors are varying making the car think it has a bad cat. Does the car run normal?
even if this isnt the problem it will still help with power and fuel economy
I pulled that same code "po430", it was the cats. I had them replaced under warranty.

