Most turbo failures are caused by oil starvation, oil contamination and/or foreign object damage. Turbochargers with manufacturing defects tend to fail “out of the box”. All CTS Turbo turbochargers are manufactured to meet or exceed OEM standards. Here are the most common causes, which are very easily identified during professional inspection after disassembly: Engine oil contamination: small carbon particles can enter the engine oil and erode the components inside the turbocharger. Over time, the tolerances will increase and cause the turbocharger to fail. The evidence of this failure is the “dentist drill” sound coming from the turbo and evidence of oil leaking from the turbine end seal. Results: oil leaks from the exhaust side of the turbo, burning oil smell, loss of power, complete seizure of the turbocharger, catastrophic failure of turbocharger. Prolonged engine idling can create a vacuum with the turbine. Results: oil leaking into the intake (cold) side of the turbocharger. Hard acceleration from cold start may not give the oil enough time to circulate, causing oil starvation to the turbo and engine bearings. Results: turbocharger seizing, bearing failure, catastrophic failure of turbocharger. Just don’t do this. Hot engine shutdown can cause carbon build-up in the turbo, leading to bearing failure. This is prevalent on high-mileage engines. It’s easy to avoid this. Over-speed, over-boost, brake-boosting, anti-lag: This is a very common cause of failure, as these conditions will lead to oil starvation (or even a mechanical failure).