I Am Frustrated

I approached Audi Centurion after I experienced an engine warning light and a rapid vibration, I was told that cylinder No.3 was misfiring and that they could clear it however not advisable (07/05/2020). We booked the car in and I received regular update on where they are with the car and that the issue is the COIL, it was replace and I collected my car a week later. 02/06/2020 I experienced same ‘an engine warning light and a rapid vibration’ took the care to have is checked out at Super Quick as I was not in Gauteng at that time, the diagnostic results was that cylinder No.3 was yet misfiring again (as per attached picture). I was back in Gauteng 08/06/2020 and attempted to contact Audi Centurion several times and eventually got hold of the servicing manager on the 10th of June and booked the car in fir the 11th. (This is where the service absolutely horrifying). Called in on a Saturday 13/06/2020 and on then was I told that they suspect the injectors, my Question was ‘as specialists, how could this be missed in the initial diagnostic testing?’ While the vehicle was in, at no point did I receive a call confirming nor updating me on anything, I have to call back ever when they’ve promised to give me feedback. I became a mediator between the Audi and my warrantee provider(innovation) and in my view this is not how subrogation works nor intended to be. fast-forward a week and a half in, I called the servicing manager and informed him of my dissatisfaction with the service, he intervened and collected the car 02/07/2020. The car drove well and I was confident that all was well until 10/07/2020 ‘an engine warning light and a rapid vibration’ immediately drove to Centurion again, spoke to the servicing manager and stood there for over 20min waiting for a technician to check the car, the diagnostic came back and said that cylinder No.3 was misfiring. At this point I’m frustrated, questioning the brand “Audi”, I don’t trust the brand anymore and when I request to speak to the servicing manager he miraculously went into a meeting. The names of Audi representatives I dealt with are: Madia Mdu Martinus