Catalytic Converter Replacement: When is it Necessary?

Hi,

If a V6 TDI engine has a turbo failure and suddenly blows 2.5 liters of engine oil through the exhaust, and then runs perfectly fine again with a new turbo, what is the likelihood that it will pass the next emissions test?

P.S. I've never seen a blower shaft so loose, and also these bent impeller blades (it looked like an M8 screw had gone through from the intake side to the exhaust side).

Actually, the chances are quite good, because the pollutants that the catalytic converter was supposed to convert are not even being measured.

Best regards, WarLord.

The emissions test doesn't tell the whole story. I would still like to take the car on the highway and really push it, so that the emissions test doesn't release all the deposits and measure what the exhaust is actually producing.

Hi,

'Get on the highway and really floor it. The cars that have had turbocharger problems in the past have always passed the emissions test without any issues. Even the Audi S4s that had turbocharger damage have passed the test successfully.'

Best regards, Christian.

My first ALH in my Golf 4 also broke down (piston failure). Before that, I was consuming more oil than diesel. It was okay for the workshop... *sigh*... until it turned into a 3-cylinder engine.

Fact: The entire engine, including the turbocharger (without injectors), was replaced. The catalytic converter remained in place. I never had any issues with the emissions test.