When cruising car runs fine but if you lightly ease off the power car starts juddering. To stop this you take your foot off completly or push down hard. In the second option you get some black smoke out back then car takes off. Anyone any ideas.
try comma diesel injector magic from halfords,a bottle in half a tank & do at least 250 miles before you top up. the egr may need removing & cleaning. You can buy a cleaner in spray form in the trade for EGR valves.