I've figured out that what is actually happening is the transmission is momentarily dropping out of overdrive, which is why I see a momentary 200rpm spike on the tach.
After cleaning the IAC with carb cleaner, it ran good for a short while, but then started acting up again (especially when the A/C is on). So, I got a new IAC sensor from NAPA. They assured me it was the correct one. Looks the same and mounts the same. Only slightly different plunger to control air.
I installed it, and it runs worse than before. Started up the motor, and idled fine, but jumps up 700-800 rpm when the steering wheel is turned. Also is worse when the AC is running. Then it will jump in RPM when I turn the steering wheel (while at a stop), then stall.
I tried wiggling the connection to the IAC with the motor running and can hear it opening. It seemed like it would cut in and out if I wiggled it right. Also, seemed like it ran better with the IAC unplugged.
Monday, May 2nd, 2011 AT 12:54 AM