I have had oil leaks at the oil feed line connection to the union on top of the turbo and the washer under the union breaking and leaking. You can buy a replacement pressure seal for the end of the turbo oil supply line, but will have to remove the line from the engine and saw off the old seal first. The cone seal costs about $6, but be sure the line is completely clean and there are no metal particles left over from cutting! A new line costs about $85 for my 1Z engine but the seal is hollow so if you over torque it, it will leak oil very quickly since it is under 60 PSI pressure! Do not mess this up or your engine will be ruined in short order! I replaced the line shortly after buying my Passat in late June. I replaced the seal and a broken washer under the union 2 weeks ago. Just a little present from the former owner....he used an aluminum washer under the union which cracked and all the oil leaked out. The washer is supposed to be copper I found out. I found a 3/8 copper washer from a hardware store and filed the inside diameter just enough to get it over the threads on the union. The copper gasket from VW is too small in my experience! As for the seal on the end of the oil supply line, since I realized it was hollow, it is essentially a one time use item. The replacement seal is solid steel and will not collapse like the seal you get on a new line. Hope my hard won education can help you prevent another loss of engine oil!
