Won't start

Seems to run fine at 2800 rpms and higher but still won't start without the OBDII scanner hooked up. And, as soon as I unplug it, it quits.
I pulled the IACV off and turned the key to on. It seems to be ok but I am not totally sure what I am looking for. It moved and I could feel a slight vibration in the solenoid of it. Pulled the throttle body off and made sure the passages were clean (they were).

Hi guys, I had similar problem. Accidentally I plugged in computer in OBDII port to see if I can read codes, cranked the engine and it started. Without diagnostic computer connected to OBDII port it would die right away. While running I read code P0505 - fault of Idle Air Control Valve. Also car was running erratically during low RPM idling. But because Car would not start without diagnostic computer connected to the OBD2 port - it means computer through the port provides ground to PCM to start the car. Answer is - while doing repair you have a ground wire undone somewhere and did not secure it well after reassembly. In my case wire I did not secure was under the air intake box. During assembly I pried the bolt slightly but forgot to tighten it with the wrench. I spent a half a day looking for problem and researching it on Internet, finally after tightening this G102 ground connection - all went smooth and car starts without a diagnostic computer connected to OBDII port. Hope it helps someone with similar problems.