Hi
I've owned my 2016 2.2D for 2 months now and I've noticed in the past two weeks that, either when coasting or decelerating, a judder develops around 1500-2200 rpm. Under acceleration it performs fine. Coincidentally, or otherwise, I filled up with supermarket fuel around this time but I've never been convinced that there's any difference between off-brand and brand regular fuel. I didn't notice it before.
Also, is it normal that I only get a surge of acceleration from the turbo around 2200rpm? Could my problem by the "sweet spot" at which the turbo is asked to come in? Any explanations on how the two-stage turbo should work and how the driver experiences this?
My working theory is fuel filter or the ECU's management of the turbo around this rpm.
Thanks for any advice and general insight.