2.5 N/A BLACK SMOKE Advice needed please !

Hi everyone
I have a 2.5 N\a in my series 3 on tick over there is very little smoke maybe just a small puff of BLACK smoke ever now and again but when she is running on half or full throttle (in any gear) there is a steady flow of BLACK smoke comming out !!!

I am guessing this is unburnt fuel (she does seam a bit heavy on the fuel consumpsion) ??
Note there is some redex in the fuel at the moment if that makes a difference ??

Should i have a play with the fuel pump and turn it back slightly or is there anything else i should do first ??
Regarding the adjustment of pump timing do i just slacken the 3 bolts turn the pump slightly and see what happens

Many thanks chris

I think you are right, black smoke excess fuel, back to basics, Clean air filter? Leaky injectors or worn, out of calibration fuel pump, too far advanced fuel pump timing. Valve clearances too tight?
There could be other factors like engine condition.
A few things to consider.