Almost 90% percent of the time it's the MAF sensor. Have you cleaned it lately? They are so sensitive to everything that anytime you change air filters or mess with that tube it fucks it up. Obviously you can unscrew it and pull it out and give it a good cleaning or you can get at it with a cleaner and a straw attached. If all else fails remove the positive cable from your battery for about 5 minutes then put it back on and run it around and see if you have the same problem. Also you can pull codes on that car without a reader!

http://www.fordfuelinjection.com/?p=13

Let me know after all of that!