This particular Volkswagen Repair found a turbo charger that failed. It was severe failure where the impeller came off the turbo and large amounts of oil went through the turbo into the exhaust. We let the customer know when we installed the turbo that the catalytic converter would most likely have to be replaced as well, but sometimes they can burn off the oil and survive the trauma. Funds were tight for the customer so he elected not to do the catalytic converter at the same time as the turbo. In this case the patient could not be saved. A few months later the customer returned with a check engine light on and a little more money in the bank. We installed the new Volkswagen catalytic converter, and now the car is running clean with no check engine light.