funny noise -freelander td4

Hi guys.My landy has been going so perfectly until one day I had a funny noise from just below the pedals.I put it into neutral and rave it and still the sound is loud and clear.I suspect the turbo though it's still haven't lost power neither is it smocking.It's a 2003 td4 BMW engine.please help.

Get it looked at by a mechanic ! Could be a simple clamp coming loose !!

I took out the suction and air discharge pipes from the turbo and both has some oil in them,could that be a clue as to where the noise came from.

It might be, but on the other hand it might not. It's perfectly normal to find oil there. What sort of noise is it? Is there all the time?

The noise starts only after driving for a while,it comes and goes,but its louder when I push the revs upbut at idling it's much quiet.so how does the oil get there.

Hi everyone.I got to the bottom of the problem and after changing all 4 injectors,the noise still happened,I then discovered that cutting off one wire from the fuel pressure regulator,the noise disappears,I then bought a new pressure sensor,put back the wire,problem solved,drives nice again.
Thanks guys for your co operating.