Getting rid of the cats is not going to "fix" this code. In fact, it will cause other codes, the ECU needs to see the O2 sensors and the ones after the cats need to have different values than the ones in front of the cats or they will throw codes. If this problem is age related then it could be the knock sensor has a finite life or there is a wiring issue that surfaces after a period of time because of corrosion. Is this problem mainly in one area of the country, dependant on the # of miles, what do the cars with this problem have in common? The gas supplied in the area, the local temperature maybe? The shop servicing the cluster?