At speed and accelerating there is miss. Like a duff plug or similar, but they have been changed still problem there. Have had the car to the garage and computer plugged in; it says no problem. But there is no substitute for experience. This has only recently started over the last month or so. The car 52 plate only has 45k and I have had it serviced since new. Anyone with similar problem?
Possibly a plug lead arcing out. If you can, have a look in the dark, you may be able to spot a spark between one of the plug leads and the engine block. If you do this and see a spark, don't touch it. These things are called High tension leads for a reason.
Sea Jay Pea and Full Tilt may be onto something. Will give each of these suggestions a go and will get back to you.
Seafarer long away from your suggestion just now. I will try the legitimate means first as I actually quite like the car. Cars do not write themselves off, generally the driver has a lot to do with it. Hope your sis is ok.