To All, appreciate all the info and site. My friend, 87 CRX Si/black, is best car I have ever driven, bar none. Owned since new and not trouble except for the hail damage. Have worked on cars for 63 years so new better than to let it sit in new barn for 3-4 years while building barn and house. Of course had the dreaded hunting/searching/galloping idle when I now have time to think. Read and considered every one of the 100s articles about what to do. Would start instantly, idle up at 2000-2100 rpm, slowly come down, then gallop like crazy at 300-2000 rpm. Would continue for long time, then usually would finally die. Runs fine now after new plugs, cap, rotor, wires, oil, coolant. I knew timing and valve lash was good. The fix: (1) removed the fast Idle screw, spring, washer, and O-Ring. Cleaned the thick, greasy-like material in bottom of chamber with cotton swabs. Final swabs were dampened with throttle body cleaner. Took perhaps 20 swabs. Cleaned screw, spring, washer, then replaced O-Ring with #5 (3/8" x 1/4" x 1/16"). (2) removed cap, black "bucket", large spring, and plunger assembly from IACV. Not much to clean, but especially cleaned the bottom of the black "bucket" including the orifice where the plunger seals vacuum as car warms. Replaced O-Ring at bottom of black "bucket" (15/16" x 13/16" x 1/16"), and O-Ring under top cap (Honda part 16075-PE2-005, 31.2 OD). Lubricated threads on black "bucket" with light grease, then tightened to a easy stop. Did not muscle it. Result: Car started like electric switch, went to high idle (~2000), came down slowly to 600-700 rpm. Opened FIV about 1/4 turn. Drives really nice. I think this is the answer to almost all the searching idle problems.
Hope this might help. Have a good day. Now if we could just find some fenders. Bill T.