Management light and stalling

Hope someone can help even a bit and its greatly appreciated if you can.

My car haas been running a bit sluggish and throaty during this cold weather and seems to be no action or very limited from the turbo. In Jan this year the same kind of thing happened and i had 2 sensors replaced under warrenty.

This morning it got worse and when my fiance took the car to her work the management light and battery light had come on and she said it stalled at a round about.

AFAIK the sensors were boost, MAF and N75 its 2 of these 3. would they still be under warrenty?

I have ordered an Autel Ms509 OBD 2 scanner too help as im fed up paying a garage now.

its a 1.9 tdi pd100.

Thanks