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It did idle lower, and the revs did not hold like they did.
Other than that, it stumbles on startup and doesn't feel any better.

I'm not convinced that plugging the hoses or gutting/disconnecting the IAC is a good idea for the simple reason that doing that completely takes away a function that the IAC exists for and that the ECU controls.

Considering the mutually opposing issues of smooth idle, emissions control, drivability, and so forth, I would rather limit the function of the IAC bleeding air into the intake manifold than defeat the function entirely. Thus, my trials with various size openings in the IAC air circuit.

Don, y'all
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