I recently bought a 57 plate 320i coupe. The car had 26k miles on the clock and a full dealer history.

After about 2.5k to 3k miles of use, I started to notice some hesitation when accelerating. It's more noticeable when pulling out of roundabouts or acceleraing in a straight line. The car shudders and the rev counter is jerky. It's not severe just irritating.

The car recently went in for a main dealer service and they couldn't find anything wrong when they test drove it. I have an opp to demonstrate it to them this weekend, but would like some pointers as to what may be causing it.

HJ's CBCG points to possible issue with corroding crank shaft sensors. I will point this out to them but is it potentially something as simple as a MAF sensor or similar and if so, wouldn't it show up on diagnostics?