Limp mode

[bazlad85]

I've got a problem with my a4 2L 170 se. It randomly goes in to limp mode. All of the fault codes point to the turbo but i had it removed and tested and the fault couldnt be re created. the car will run fine for a while, this could be days or weeks and then randomly goes spazzy!!!!! I'm thinking its maybe a sensor from the turbo, any one who has any ideas please let me know because its frustrating the hell out of me.