HIS4

I've been getting this code for a few months now. At first, I would clear it, and it would come back within a few weeks. Now it's starting to come back within a few days. I've replace my primary O2 sensors because I had some codes for those and those codes cleared once they were replaced but this one doesn't seem to go away. I was going to try replacing the secondary O2 sensors but some people have been saying it's the cats going bad. Here's the actual log from VAG-COM.

Sunday,05,August,2007,12:31:35
VAG-COM Version: Release 607.3-UD

Control Module Part Number: 8D0 907 551 M
Component and/or Version: 2.7l V6/5VT G01 0001
Software Coding: 06711
Work Shop Code: WSC 42106
1 Fault Found:
16805 - Warm Up Catalyst; Bank 1: Efficiency Below Threshold
P0421 - 35-00 - -

Readiness: 0000 0000

Bracketracer

if that's your only code, then yes I would say bad cat

HIS4

Yeah that's my only code.

Dodge2Dub

I just got this code after two months of having my second set of cats on the car.