engine light on Ford Windstar 2000

Engine light is on in my 2000 Ford Windstar SEL van. I took it to Autozone and had codes run. It showed a problem with EFG code.
They told me I would need to take it to the dealership and have it put on a diagnostic machine to see what part I needed. Does anyone have an idea what it could be? It sometimes has power surges and sometimes hesitates to start. I would like to have an idea of what kind of costs I am looking at.

Thanks,

Starr

Need that actual numerical code(s) that were read to offer answers

We currently have our 2000 Windstar in the shop because we ignored that warning light (it wasn't on all the time). We were also having problems with it not starting, and sometimes going up a hill, it would clunk into gear. Well, the entire transmission needs to be replaced. I called Ford, and they won't do a thing about it. I bought it used and it is out of the regular warranty. We have about 70K on the car.

Hope this isn't your problem also, but after some web research, many have had this same problem.