Purchased a 1998 1.8T passat with a blown engine for $1000 and I rebuilt the engine over the summer. There is a lot of chatter about oil sludge destroying these engines, this is completely false! Oil comes through a metal tube around the back of the engine over the catalytic converter, exhaust manifold and through the turbo charger. Non-synthetic oil cokes (forms hard particles called turbo-turds)inside all of these components. Eventually enough of this coked oil breaks free, clogs the oil sump screen and oil starvation occurs. This is what causes the vast majority of 1.8T engines to fail. Either VW engineers are complete idiots or this is an engine designed to fail.
While rebuilding the engine I also replaced the metal oil feed lines, and installed an oil pressure gauge. For $1000 + $1500 in parts I had a 89 passat is a rebuilt engine. My wife drove the car for about 3K miles and the automatic transmission failed! The internal D Clutch snapped in half!
This is a widely know problem with the ZF TipTronic transmissions used by Porche, BMW and VW.
The oil line as you described with its routing is quite interesting. My 97 Volvo turbo uses a very short and direct route to get oil to the turbo, and is still going. Seems the war would have taught the Germans a lot about oil and lubrication. They came away learning that money beats soul every time.
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