Surging issue

[3StrokedBLOWN06]

I have an 86 capri 5.0 and I hit a bump, after that I noticed a surging problem (which has been off and on for a while) come back.. Before this I always cleaned/replaced IAC.It used to fix the problem. But this time I tried cleaning the IAC,TPS, and the throttle body, Ive replaced spark plugs, cleaned the distributor cap, tested the IAC by unplugging it and seeing if the idle drops (it does), checked for leaks (dont know how good of a job I did), and the car still wont idle right. When first starting it idles at about 3000 for 2 seconds then goes down to 650. Then if I drive it normal it stays at 650. but if I punch it, it drops to 0, then up to 500.It is surging the whole time. The car has died twice and I cant figure out what the hell its doing. Sorry about the long post I just have no idea how to fix this.
Im getting desperate. lol

 

[BlownFiveLiter]

I moved your post out of the Surging Idle Checklist thread, since that one's more meant to serve as a guide to fixing surging issues, not so much for asking questions in. Start with the first post in that thread and follow it along, step by step. It will very likely contain the solution to your idle issue.