I recently had water get into passenger back and front floorboard due to clogged drain (02 S6 Avant). Now ESC and ABS warning lights r staying on.. Tiptronic manual shift is out and clunks when shifting into reverse..also seems severely under powered when taking off.. any ideas on were to start?

There is very little traffic on this board. You will do much better by posting your question on the board designated for your car.