So if I do a full Emission removal with the exception of the BAC as well as the throttle body mod, Do I need to go stand alone? If yes, do you have constant engine lights and bit codes with all that stuff gone?

 

S4 yes you can do it with the stock ECU and be fine, s5 will give you the check engine light

It will also smell like its running SUPER rich (especially if n/a)

 

It's and s5 turbo

 

is the engine running badly? If it's running ok why mess with it?

 

Why would you do this? There is NO power gain to an "emissions removal" beyond what you achieve by removing the cats.

 

I did not modify my throttle body.
I deleted my rats nest and air pump, no engine codes.

I did gain an alternator pulley problem, and exhaust that smells aweful.
I deleted the rats nest and solenoids to simplify my system and avoid possible problems after my engine swap.