i'm in NJ which has CA style emissions. for some reason, they can't or won't put my car on the dyno but they do test at 2500 rpm, so i guess that did heat up the cats.
question about the comment on not comparing against two years ago - would 2 yrs and about 20k mile age the cat converters significantly considering the car is only 10 yrs young? see how it went from 8 ppm to 160+ ppm and from 0% CO to .52% CO. i'm inclined to believe that there is some other failing component.
would an exhaust leak affect it that much? are leaks before the cat the only ones to worry about? we did have a harsh winter which is a killer on exhaust systems...
1993 300e-2.8 - gone now <sigh>
"Do not adjust your mind, it's reality that's malfunctioning"