Thank you all for your replies to my earlier IAC and idle posts.
Car idled at 2000 rpm although I cleaned IAC inside and out and it tested at 20 ohms between inside pin and either outside pin, 40 ohms between outside pins. IAC opens and closes with 12 V to inside pin and grounding alternate outside pins, but air leaks in and out through the connector end. Female connector on the wiring harness shows 12 V between center connection and either outside connection with engine at idle. Then, car would not start, but an new ignition module fixed that. Still car idled at 2000 rpm until I disconnected the IAC and manually closed its valve. I drove the car to get another IAC and it ran very well until boost shot up and down. After that, black smoke (not blue) blows out of the tailpipe upon acceleation and boost will not rise. I looks like a bad AMM, but the car runs fine before it goes into boost. Even if I put a new IAC with the ignition module, what explains that black smoke and lack of boost now? Thank you for your help.