I know someone had this same problem a month or two ago but I cant remember who. Anyway it just started happening as I was on my way down from York tonight. At first I thought it was my imagination or Id gone over a bump in the road, but what happened was just for an instant the engine missed a beat. Ive had weird things like this happen before; while racing Simon and caning the nitrous the engine cut out totally when I let off the power, today it was doing it while the engine wasnt under any load really just normal slowish driving in A1 traffic, usually at only a quarter throttle, gentle acceleration - it would just cut out for a fraction of a second, enough to feel the jerk, then come back straight away.
Any ideas? Looks like an electrical problem to me cos its not a constant thing and keeps coming and going.