Fabia 1.9TDI missfire

I have had my 2005 Fabia 1.9TDI for just over a year, previously I had a Polo 1.9TDI. My Fabia has just started to play up occasionally, it always begins  by what appears to be a misfire and normally occurs when driving quickly ie motorway, dual carriageway etc. This may last for a few seconds or maybe a bit longer if I take my foot off the accelerator it sometimes goes away. This is followed by the traction control warning light and the engine management light coming on together. If I stop and restart the engine the traction control light goes out but the engine management light stays on, the engine will now run perfectly smooth with full power and performance. After a couple of journeys the engine management light goes out and all will be fine for a week or so. I travel about 450 miles a week to work so mileages between it happening are fairly high, but the number of stop starts are low. The car is well maintained but with my current work it is difficult to get the car to a garage for diagnostics (I live and work miles from any garage). I have not tried pressing the ASR button to turn the traction control off but have read it is troublesome, does anyone have any ideas?