Not me, the car... cdti 150 auto est

As I have mentioned on one or two other threads, I have had the odd occasion when I get what feels like a misfire ["cough"] on accelaration. It got worse the other day after sitting in traffic. It also seems more prevalent if I use Shell V_power Diesel as opposed to ordinary Shell diesel. I get no spanner light come on and after a bit of a thrash, it usually clears after a couple of minutes.

Yesterday I reset the ECU by leaving the battery off for an hour or two and since then, I have not had any misfires today. The car is still a bit sluggish under 2000 rpm but otherwise seems ok.

Has anyone else experienced irregular running after changing brand/strength of fuel and is this likely to be the cause of my problems or is it likely to be something else do you think?