Dear I am a similar patient like you...I got it repaired twice but in-vain. Final verdict for me is that there is some issue in the head of my Charade G11 original engine. On AC temperature needles goes beyond half the mark in just 10 kms running, lots of load on engine. Otherwise it is awesome, no heating issue in engine and petrol average remain at 14km/lit.
Currently I have left the matter as it is and living happily, I will see again after an year or so if engine dies further.