300 Tdi Turbo noise under pressure

Hi All,
Sorry if this has been already addressed on a thread but could not find it.
Have a noise when the Engine is under pressure ie when turbo is fully deployed (uphill/accelerating hard on motorway). It sounds like a roar, maybe a leak or is it when the waste gate operates?
Notes -
Only occurs when warm.
Turbo boost not measured
Performance ok but flat when noise occurs.
Waste gate seems to operate (moves) at about 15psi when operated with compressed air.
Tried loosening the top hose clamp to see if made noise worse - made no difference.
Have changed manifold gasket as was oily around number 1 cylinder - made no difference.
110
So do I have a leak or is this normal for a 300 tdi??

Thanks in advance

Bit of an update, Managed to pressure test hoses and intercooler - held 20 psi so no leak there, also disconnected the air cleaner at turbo - still made the noise. Thinking waste gate or leak on inlet manifold - will report.

Undid the air filter hose still makes the noise without airfilter in circuit - must check the turbo pressure - thinking the noise is actually coming from the Turbo itself. to be continued

MFC said:

Undid the air filter hose still makes the noise without airfilter in circuit - must check the turbo pressure - thinking the noise is actually coming from the Turbo itself. to be continued

Click to expand...

Have you tried taking the inlet hose off the turbo and checked for movement in the turbo?

Yes - turbo turns fine - bit of end float - seems to be ok! - thanks

Latest - Pressure on boost seems ok around 15psi - nothing too wrong there. Just ordered new set of hoses just in case. Getting very confused

Can find the source of the noise, Now have new hoses and clamps, even took the Intercooler out od circuit - still made the noise. Took the old turbo off, looks like there is some play in the turbo but too much? Decided to order a new one see what happens, Will be really disappointing if noise is still there with the new one!!!

The New turbo arrive and fitted, not without drama as even being careful and using a torque wrench stripped out a inlet manifold tapping, hellicoil fitted and turbo installed. Was really worried on the first drive that the noise will come back but all gone. Strange old turbo worked fine but noise present, at least we now know the source - old one would probably have lasted years but now we will never know!
Anyone in the Market for a functional but a bit noisey turbo??? Finally end to the saga - will try and post other mods made for the upcoming trip over the Pyrenees

MFC said:

The New turbo arrive and fitted, not without drama as even being careful and using a torque wrench stripped out a inlet manifold tapping, hellicoil fitted and turbo installed. Was really worried on the first drive that the noise will come back but all gone. Strange old turbo worked fine but noise present, at least we now know the source - old one would probably have lasted years but now we will never know!
Anyone in the Market for a functional but a bit noisey turbo??? Finally end to the saga - will try and post other mods made for the upcoming trip over the Pyrenees

Click to expand...

Pleased you got it sorted. Old turbo was obviously on the way out.