A couple years ago I was able to purchase one of the last Audi cars with a 6 speed manual transmission. This was a 2015 B8.5 S4 with 33,000kms. Glacier white with black interior...it was sporty and luxurious. When warranty was up we would add a Merc Racing Heat Exchanger, Upper Supercharger Pulley, Integrated Engineering Stage 2+ tune which pushed the car from 333hp to 440hp. A catastrophic Dual Mass Flywheel and Clutch failure netted the car some downtime during Covid while waiting for parts. While down we upgraded to a Southbend Stage 3 Daily Clutch with LWFW. We would also add JHM, CTS Turbo and CTS parts. Test pipes, relocated High Flow Cats, crossover and mufflers to give the car an exotic tone. That was 2 years ago Putting low miles on my car from 2017, the input shaft bearing on the transmission also was failing but wasn't caught at the time. Getting worse with time and mileage...it's back down in the shop but we'll get the bearings replaced and get this rare S4 up and running soon. Here are pics and vids of the build.....

Stock with painted black 19" rims against a beautiful backdrop:


Stock with 18" bronze winter rims and studded winter tires for our Canadian climate:


CTS Cold Air Intake...this helps to add the Supercharger whine which is intoxicating:

 

S4 getting transmission yanked for failed DMF and Stock Clutch:

 

Transmission:




Test Pipes:




Relocated HFC

 

New exhaust components:






Leading to Stock muffler at the time:

 

Installing new rear wing to add some sport to this S4:




before spoiler:


after spoiler:

 

Stock exhaust:


Aftermarket and one of a kind exhaust:


Magnaflow X-Over Resonated with Corsa Mufflers:

 

Stock Exhaust with CTS Turbo CAI to allow supercharger sounds out:

 

Different angle to show stock S4 exhaust with supercharger whine solely from CTS Turbo CAI - this car was woken from this part swap!!!

 

Aftermarket exhaust parts to stock exhaust cold start (sounds like a tractor when cold):

 

Aftermarket parts revving...doesn't sound like a tractor but has a tinny sound (like E46 BMW M3):

 

Full Exhaust system done....the Corsa Mufflers with the rest of the system pulled this exhaust note in perfectly...low tone at idle....sounds exotic at high rpms...this is the 1st start after exhaust work:

 

Prior to this here were a couple exhaust videos with stock mufflers to show difference in this vs Corsa Mufflers:

 

Stock Mufflers swapped out for Corsa Mufflers....sounds amazing:

Full throttle acceleration to show exhaust note:

 

@fstr n u
Nicely done !!

Johnny

 

So shortly after the exhaust install I had a sporadic ORANGE check engine light come on.
OBD II codes were:
P013a
P013c
P2271

The light would come on for a couple hundred kms then go out....then come back on. No drivability issues or anything...just an annoying light. I have been researching and talking to tuning companies, etc and thought we would start with replacing the 76.000km rear 02 sensors that are plugged into CTS Turbo O2 Sensor Defoulers. As of now the dreaded annoying light is finally out. The mechanic we spoke with mentioned the driver side one seems to have been more heat affected than the passenger which speaks to the code I pulled: 02 Sensor Signal Stuck Rich - Bank 1 Sensor 2