Most GTI turbos that die young aren't defective — they're starved or coked. The turbo spins on a film of engine oil at huge speed and heat, and dirty oil, a blocked feed line, or shutting a hot engine straight off bakes that oil into carbon — "coking" — that wrecks the bearing. A few habits make a turbo last the life of the car. See Turbo Replacement DIY for when one's already gone
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