Diagnosing Smoke Issue - 300TDi

Ok so mine puts out loads of black smoke when quickly putting on the power or after changing down. And particulary when changed down in low gear flat out trying to get up a sand dune. Otherwise not really any smoke. Done it for quite a few thousand miles! Garage says no problem. Does anyone have any other ideas.

depends on amount of black smoke ,but it is normal for those turbo engines to pump out black smoke out when you boot it while turbo catches up with injector pump

When I ease off the throttle black smoke stops instantly, but while booting it there is a lot. I can see from the wing mirrow the smoke rising away. There is no loss of oil on the dip stick even after long periods. Another tdi put out little smoke!

black smoke is fuel burnt with not enough oxygen , check air filter ,turbo/inter cooler pipes for loosing or restricting air ,or fuel pump might have been tweaked to give more power/fuel

Thanks JM for info. Even in sand fuel consumption is better than the others, though air filter does get clogged up quickly despite raised air intake or will raised air intake slow air travel. Not sure if fuel pump tweaked but engine seems sluggish particularly so on pickup.

raised air intake shouldnt cause it,worth checking pipes arent collapsing on suction side of turbo and split on pressure side ,sluggishness can be caused by a few things and its wise to start of with well serviced engine before trying to fix it ie filters ,tappets ,timing ,slackening front banjo to see if copious air free fuel is reaching pump (fitting a clear plastic pipe between filter and front banjo is a useful addition to be able to see fuel ) fuel pump can be put to its best by fitting a 9.5 drill bit fully into pump through pulley then slackening the 3 bolts and holding center nut clockwise against the pin then retighten the 3 bolts ,try engine ,you can then repeat using smaller drill bit 9 then 8.5 then 8 etc till diesel knock becomes apparent then go back one larger drill size till knock goes thats optimum pump timing and can be quite noticeable in performance

Thanks again JM will take this all on board and see what can be done.

Regarding the original smoke, I have been advised (From here and a few people I've spoken to about it) that it is most likely to be overfueling when cold, now I know that fuel can also be light coloured smoke as well as black. Since there's not been any massive oil loss in the time I've had it, I'm inclined to believe that

Have you checked the timing is correct with locking pins??

my 200tdi was doing exactly the same and what i had done was i thought i was being clever by borrowing some john deer engine oil from work and changed the oil and it almost instantly smoked on low rpm so done a bit of resurch and found that basicly it was to good grade of oil changed it back to old fasiond oil and solved the problem so might be werth a thought what oil you have got in it