S4Roper

Long time reader of these forums, but it's been a number of years since I've had a B5. I recently picked up an 01.5 S4 with 104k, impeccable maintenance and service records with mild upgrades (Revo stage 1 tune, AWE intercoolers, Hotchkis frt. and rr. sway bars, Vogtland springs and Koni adjustables). I've put on about 1,000 miles since getting it and the previous owner was kind enough to run VCDS log for me before shipping it, which came back clean. Skip forward to yesterday. On the way to work, the CEL came on. Ran fine (strangely the car is getting about 25 MPG) so I pulled in to work and got out my BlueDriver scanner. This is one I use for work, but I'm in the process of getting a Windows laptop so I can run VCDS (I'm a MAC guy, so this is an uncomfortable but necessary step in ownership). I got a P0421 code for Bank 1 Cat Inefficiency. I cleared it and drove it home, back to work and home. I ran a log on it tonight (no codes and readiness appears to be set) and thought I'd ask if anyone could look these over and give me their opinion. I know downstream O2's could be a culprit, so I figured I'd look at the values and I thought at operating temp, they should be pretty consistent, which I think Bank 1 is. But Bank 2 does something similar. If anyone has some time to look these over and give an opinion, I'd appreciate it.

https://docs.google.com/spreadsheets...rue&output=pdf

Sorry if the link isn't working. Can email to anyone that is interested. Thanks for any help you all can provide.