I have a fault code thats come up saying egr valve. the symptoms are lots of black smoke through every gear and sometimes a bit of a splutter or flat spot when at a steady speed, and now and again it goes into limp mode, but if i stop and start again its ok. I have had egr valve off and manifold it was really sooted up. so i cleaned it all up and mechanically it works fine, put it back on nut there is no difference. it seems like its running very rich , and im getting about 31 mpg. garage told me egr valve but thats easy for them to say that and when thats not it , it must be something else. i want to try all other avenues first before i have to start spending stupid money for these parts.Anyone help please.[/b]