lambda sensor and the dasc

[m3nut]

After fitting the new 3.4" pulley to my dasc, the lambda sensor packed up?

A few weeks back on the standard pulley I made a trip about an hour on the motorway (70-80mph) and was getting surging during light boost conditions.

Now the pulley has been fitted the first long trip (again same hour on the motorway) still got surging during light boost but this with time power loss??
Made it home, but by the time I got there it would not rev over 3k without total power loss!

The thing is I was associating the power loss with the surging as it seemed to be just after. The tick over was fine steady 700rpm

Got it hooked up on the code reader, and came up with o2 sensor as well as a long list including miss fire cylinder number 2/ maf ect.

The spark plugs were black and the lambda sensor was too. I have since replaced the sensor and the car is now running without any fault codes

But my question would be, have any of you guy's running the charger had problems with the car running rich and may be destroying o2 sensors or could it just be the extra boost has speeded up the faulty sensors life span?

I need to get it back out for a long run to see how it performs