My car is a S4 B5 pre-fl so i don't have canbus.
Yes you do. Not in the OBD socket but PTCAN is there.
And yes it can be easily done.
Easiest way is to use some app that can read raw CAN frames and has a visualization display.
There's a lot of those. Hook it up to the PTCAN, maybe enable some more messages in the software, and job done.
Of course not all parameters are there, if you want more parameters you will need to request them via K-Line.
