Renault Duster 1.5dci Dynamique 2014

Around a month ago I have taken delivery of a 2014 Renault Duster 1.5dci Dynamique 4x4. It has only 75000km and was told that it is an absolute gem of a buy. On my first long trip, 100km from home there was a sudden jerk, the esp light came on and then all the other lights on my dash came on (stop engine, glow plug symbol, fuel pump/toxicity) etc.

I then took it to Renault to fix. After diagnostics they said it was the injector that was an issue. It was replaced for almost R11 000 and off I went. The next long distance trip which was around the same distance it DID IT AGAIN... Exactly the same thing. Now running like a tractor and rough.

Does anybody know what this could be or have any idea how to solve it? I dont want to be forced to pay for 3 other new injectors and the problem is going to remain there. Which seems to be the most likely case.