for the last 3 months my car (1,2 56 plate) has been dropping rev's and then sometimes stalling,i thought it was cause of the winter.

on Thursday afternoon after work i started the car up and the rev's dropped to below 10 so i revved the engine a bit,i set off and stopped at the car park barrier and the car stalled.i started up again revved the engine and set off about 10 yards and the engine stalled again.

i booked it in for this morning,the dealer tested it and took it for a test drive but they could find nothing wrong.

it's got 6 month's warranty left and only done 12400 miles.

what could be the problem ?

Sounds like an idle speed control valve issue. I'm not sure how the system works on that engine though. The other thing that could be fault is the inlet charge temperature sender.