idle help

[jd2003]

i have a 93 ford probe. when i crank it up it will idle at 2500/2600 rpm's then drop to about 1200 after a min or 2, when going down the rode coming to a stop my car wants to idle back at 2500 before dropping back down, or it will hop around 500 to 1300 then idle down to 500. the guy i bought it from changed the fuel injecters, and bent injecter one, so it wasn't working he told me he had to adjust the throttle or adjust something to make it run right. i fixed the bent injecter. and now it runs the way i described above. also it likes to hop when changing gears any advice will be great