2006 1.6 Tdci boost leak chasing

Hi all,

Have had issues with my Zetec S stinking of diesel/exhaust and having done the injector seals and had one refail, and my local garage then do them and had two refail, I've done them again, new studs, torque and angle on the nuts, they seem to be holding currently.

But she still smokes if I stamp on the pedal,and there is a definite lack of power so I'm now chasing boost leaks. I've made a tester hose which I can fit onto the turbo inlet with a shrader valve, and I've got a compressor, but I can't get the system to hold any pressure, at all...

There is a hissing of escaping air from behind the turbo somewhere (IE, sounds like between the turbo and the exhaust manifold), and I've removed the plastic pipe across the front, and all the hose down to the intercooler and tested that separately, and that holds pressure fine.

There was slight sideways play in the impeller, but no back and forward, and it doesn't touch the housing. There was some oil in the turbo inlet which I think is fairly normal? EGR has been recently blanked.

Before I take the turbo off and have the whole system apart, is there anywhere really common for these to leak around the turbo area?