Renault not prepared to take responsibility for a damaged/faulty car

In 2015 I bought a demo model Clio IV 900 TCe. I complained about the noise coming from the engine when the car went for a service (30000km) & the person that had to investigate it, didn’t do his job properly. That person then **** to me about the problem, as it wasn’t properly investigated & assured me I shouldn’t be concerned about that noise! That noise was in fact water that was boiling, back into the reservoir for water/coolant!

My engine & turbo is no longer in working condition, due to overheating. My initial complaint was while the car was still under warranty. If it had been fixed then, it would have been for Renault's account!

I've been trying for more than 2 months to get this all sorted out. Everytime I get some contact from someone at Renault SA, it's purely just because I've been bugging the directors at the head office in France and then they instruct the local persons. After some brief contact from the local guys, I get promised some further information or communication within a day or 2. That is then also the last communication that I receive.

According to my knowledge, my Clio is a French car, but somehow I can't complain to the French HQ. It's pointless complaining to the South African HQ.