Hi Kev, im having the same problem with my pug 307. Have a look at peugetdiesels web site. There is a page on there to do a self test on the ECU. Mine is a nightmare, the dealers rekon it will cost 700 quid to get it fixed but others have told me that it is poss the BSI. There is a page on the net that tells you how to reset the BSI. I have forgotten it (it didnt work on mine tho) google ' reprogamme peugeot bsi'.
If you get any news mate let us know.
Cheers
ronnie
April 2008