rwilthil

Hi all.

Got an S8 5.2 here from a friend. Did a VCDS check last night, and it had an issue with to high values on emissions from Bank 2.
Taking a further look into the measuring blocks, i see that one cat has a lot higher temperature than the others, making me think it may be partially blocked. Also thought about exhaust leak, as this is a known issue, but i cant see that should raise the temp. It is about 100-120 deg Celsius above the others.

Anyone who knows how to determine the specific cat, meaning what measuring block belongs to who..? :-)

-Rune

90SQ

90SQ

Did you end up finding anything? I'm having a similar problem on my '08.

PaulW

Hey. I recognize the hand writing on that image!

;-)

90SQ

Well thanks for clearing this exhaust system out for me, nobody seamed to agree on witch was witch for some reason...

MP4.2+6.0

FWIW, not enough info in this thread to assess. For OP, you need to post the codes themselves--with the VCDS text description.

In particular, Audi calls the left side of the motor (as you look at it underhood) Bank 1 and driver's side Bank 2 for any motor with two heads. But for W12's and V10's it uses a four bank description for elements of fuel and exhaust, and Bank 2 becomes the rear of the left side. Gets confusing because for some parts there are only two "sides" like MAF's, but for others like cats and O2 sensors there are four subsystems along with the four banks.

90SQ

Always a great source of knowledge MP4, thanks! For my case i got a IAT sensor malfunction last time i fired it up(at -40C mind you) so since they're in the MAF's on the V10's(and probably W12 also) i ordered both to get that sorted. Will start a new thread with all correted and up to date info once i get these replaced and all details of my diagnostics.

If OP gets back to us with his that would be nice also.

Cheers!