Well, that is true of a few sensors. If you unplug a bad MAF for example, the car will probably run better.
The IAC is not a sensor though, it'* a valve. In theory, the car should stay running, but if you add a load, it might stall, or if you lessen the load, it might idle higher. The PCM will effectively lose control of your idle speed. My guess is that if you're idling and warmed up, and you unplug your IAC, and then put the car into gear, it will either stall or come close to stalling.
Hope that helps.
I'm Jon. I'm completely stock, no mods.
1993 Bonneville SSE 191,000 miles "The Work Beater" Imperfect but quite tolerable. Stock.
1996 Buick LeSabre Limited, 181,000 miles "The family car" Custom CAI, F41 Sways.
Sold/dead, but not forgotten: 1989 Bonneville LE "Bonnie, the Sport Utility Car" STB from '92-'99 Bonnie, Delco (Type II) Ignition system
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