1997 was a cusp year for Ford - some vehicles still had carburetors, most had Fuel injection. If carbed, you probably have a faulty accelerator pump diaphragm in the carb. If fuel injected, it may be the throttle position sensor or m.a.f./m.a.p. sensor. If the shop does not have the proper diagnostic equipment, you could throw a lot of money away on sensors and labor and still have the problem. The onboard computer will have codes stored in it which can tell you what is wrong. If no codes, then the computer itself could be faulty and the diagnostic equipment will detect that too. It could be something simple like a dirty maf/map sensor which could be cleaned in about a half hour. Find out if the shop has the right diagnostic equipment less than 10 years old . If they hit you with an arrogant or off putting attitude, have it towed to a properly equipped, A.S.E. certified shop.
Hope this helps and thanks for using Fixya!

Replace TPS throttle positioning sensor and clean the MAF ,