Or, the IMRC may indeed be messed up. The cable inside mine was messed up bad enough to trigger (short out) the limit indicator so that it flagged a MIL. I could operate the butterly linkage flawlessly with my hand- no sticking.
On the matter of the intake cleaner, you are probably helping your primary intake tract by using the cleaner, but the path of air will not encounter your secondary butterflies while you are doing this. The only way that you could get the cleaner to work while the engine is running is to activate the butterflies (chances are you wouldn't want to be winding up your engine, but maybe actuate the secondary butterflies by hand- the car will run like crap at idle, but it should help clean the intake system!)