I have lodged a complaint

I have lodged a complaint with Audi manufacturer because one of their dealer didn't treat me fairly. My car had a breakdown in June 2015 where they only replaced the pluck. I now have a similar problem and I am told they can't hep me because the car is now out of warranty. My complaint to them was that they have replaced only the pluck instate of finding the main cause of the problem. I am now expected to be liable for the costs which they were supposed to have covered for when the car was still under warranty.