I've been dealing with the annoying CEL for about a year now. It was due to a PO420 - catalyst effeciency low (bank 1). It didn't affect the way the car ran or performed at all. Anyway, problem solved (sort of). Tonight the bulb on the CEL burned out, so the fault is still there, but thankfully I don't have to look at it anymore. I guess it's a crappy way out, but at least the amber glow wont be annoying me for the time being.