Idle air control

Vehicle in question is a 92 with 165k.
It has a slightly rough idle and has developed a hard starting problem. When cold it will not start on first crank- turns over nicely but won't
fire. Starts on second crank or if fed a little gas will start on first crank. No CEL and I have not checked with the code reader.
I have come across some discussion on usenet that the hard start is symptomatic of a faulty IAC. The IAC has been cleaned several times with carb cleaner and the plunger seems free to travel.
Do the symptoms implicate the IAC?
Is there a test for the IAC other than replacement?
Charlie
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On Sun, 2 May 2004 10:36:57 -0400, "Charlie Bress"

Not every bad IAC is cured by "cleaning". Sometimes it makes things worse.

Not to me. I'd be more inclined to suspect a weak fuel pump, bad fuel pump relay, or a faulty check valve in the gas tank. My 92 was hard to start for about 6 months and the local service station couldn't find any obvious problems. They thought it was a bad check valve. They wanted around $500 for all the work and parts to replace it. I passed and it cured itself after a while. Maybe just some dirt got stuck in the check valve. My son has a 92 and his did exactly the same thing (including curing itself) at about the same mileage!!!

Not really.

-- Elbridge Gerry, of Massachusetts:
"What, sir, is the use of militia? It is to prevent the establishment of a standing army, the bane of liberty. . . Whenever Government means to invade the rights and liberties of the people, they always attempt to destroy the militia, in order to raise a standing army upon its ruins." -- Debate, U.S. House of Representatives, August 17, 1789
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wrote:

I did consider a fuel delivery problem, but leaving the key in the "run" position for 5 or 10 seconds before cranking did not have any effect.
Charlie
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On Sun, 2 May 2004 16:46:07 -0400, "Charlie Bress"

No matter how long you leave the key in run it will only run the fuel pump for 2 seconds, then it stops (engine not running of course). To run it more you have to turn the key off and then back on. If doing that several times cures your problem you may have a check valve problem or a fuel pump problem or an injector that leaks down too much. When mine was acting up that was what I did to make it start easier - turn the key on and off several times to get multiple 2 second pump runs. -- Elbridge Gerry, of Massachusetts:
"What, sir, is the use of militia? It is to prevent the establishment of a standing army, the bane of liberty. . . Whenever Government means to invade the rights and liberties of the people, they always attempt to destroy the militia, in order to raise a standing army upon its ruins." -- Debate, U.S. House of Representatives, August 17, 1789
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