I've been meaning to update since Friday.
I noticed the EML ping up on Friday morning followed by a very throaty sounding engine and unable to rev above 5k rpm.
I scanned the code and got P0430 - Catalyst System; Bank 2: Efficiency Below Threshold.
I suspect a large chunk of the internal cat broke off and became wedged somewhere further down the exhaust. I've reset the code but the car has no power, sounds rough and feels no where near as smooth as it should.
I'm at the stage where I'm not sure what direction to go.
1. OE cat from Audi
2. two refurbed cats from Germany as per Adrian E's write up
3. 200 cell sports cats with the EML issue coded out by MRC or similar.
I've lost motivation at the moment. The wife curbed 2 wheels the other day, then she managed to lose a fog light grill, I have a parasitic battery drain and then I have the issue with the cat!
Tempted to park her up and forget about her for a few months and hope I get the itch again
__________________
2002 S8 - Irish Green Pearl. Cat N (saved by the D2 Doctor

)
1988 E30 Coupe - Royalblau Metallic
2003 S4 Avant - Light Silver Mettalic
2016 S5 Coupe Black Edition - Glacier White