93accord

I recently ask the question of why my 93 honda acoord dies when I go to slow down. The car will crank right back up and I have noticed now that when I am driving and go in to Park, the car idle is around 1500/1600 RPMs to 900/1000 RPMs every few seconds until it eventually smoothes or sometimes doesn't. The last time I ask this someone told me to replace the ignition coil and the ICM. I did including the button, distributor, wires, and plugs. I bought this car from someone and it sat for about a year. Thier is a new fuel pump and filter, main relay, water pump, fuses, Idle Air Control (off a used honda) and about everything else I can think of. I have ran a bottle of injector cleaner through and checked all I can think of. Please give me some advise. I am about spent on the mechanics and the lack of solution.