We had a 2010 Fusion (37K miles) serviced for this throttle bottle issue last week. Our mechanic friend, who works for a Lexus dealer, was not able to diagnose or replicate the issue. We finally took it to a Ford dealer and were pleased to learn that there is a brand new warranty extension program that covers this repair. We were told it would have been a $700 repair. Hope this helps someone!
I also have a 2010 Fusion SEL (38K miles). At the beginning of January 2014,
it had a throttle body issue and the part had to be replaced.
It was very scary to have my car start sputtering and slow down to 20 mph and no faster when I was driving in a 50mph zone. The cost was almost $600 for the part and 3 hours labor. This past week, I got a letter from Ford stating that the part is defective and will be replaced. Since I already had the part replaced, I eligible for a full refund. They're supposed to upgrade the throttle body part in the spring and will replace the part again at no charge.