Phaeton :: 2005 - Start Then Cut Out?

Recently purchased 2005 5.0 V10 TDI with a blown engine! and over the past couple of months have fitted another and have run into a couple of small problems. 1 being after the change, the engine fired up and run perfect for about ten minutes then cut out! and would start for a few seconds then cut out, by mistake, after i removed the egr valve on bank 2 and cleaned it, I forgot to reconnect the pipe running from the exhaust to egr valve on the inlet manifold, car runs lovely until its connected, then back to the problem of starting and cutting out! tried a blanking plate but still the same, my only guess is that the cat might be clogged?

Second problem, is the vacuum system, The pipe comes out of the vacuum pump into a Y connector, one end goes to the brake servo got that in, then the other end runs along the back of the engine, and in my haste i cant remember taking it off or were this part went or what it connects to it would appear it can only go one of 2 ways, down the middle of the engine to a inlet manifold or down the back of the engine towards the gearbox ? My local stealership have no info where to obtain a technical data sheet on the vacuum system?