'02 Ford Fiesta Losing Power

I bought a '02 Fiesta last year and have been having problems with it on and off since. The main one being that it keeps losing power while i am driving. The engine sounds fine but there is no power to the accelarator and where the clock is on the dash comes up with EAC Fail. It mainly tends to happen when I am in a low gear but can happen up to 3 times in a short journey. I would be grateful for any suggestions before I take it to a garage as being female I don't want to be taken advantage of.

Cheers

Lots of info available if you google "EAC Fail" eg http://forums.preloved.co.uk/fuseaction-forums.showdiscussion/thread_id-22807/8b0f06aa.html

the early new shape fiesta gave alot of throttle body problems resulting in the car goin into limp mode and putting up the eac failure light ford brought out a later software calibration to over ride this problem but been a 02 could still be thethrottle body when was the last time your car was in a main dealer because this upgrades are done free during serving and may not have been done