VW Passat 2.0 TDI - VW 2.0 TDI loss of power and EMS warning light - amok

I have had the car 3 years and had no problems at all. I took the car to a safari park today and crawled round the park for around 45 mins in first gear having to stop and start. On leaving the animal park and heading to the exit I noticed that there was no response from the engine to pressure on the accelerator. after a few more yards the EMS warning light started to flash and I pulled over and stopped the engine ( and to check the manual). I restarted the engine and had same problem, limped on a few hundred yards and I stopped the vehicle for about 5 minutes. Started the engine again and everything was fine but drove it to my local VW garage (which was just closing). Told them the story to which they said the diesel does not like "poddling around" and possibly the PDF had become blocked. As they were too busy to run a fault check until next week they said to give the car a good blast on a dual carriageway for at least 10 minutes and then bring it back for the fault check next week. Has anyone else had this type of problem and was "poddling around" the safari park in first gear likely to be the cause?

Edited by amok on 06/08/2010 at 00:56