Idle Air Control (IAC) valve issue??
 

Hi.
I have an Elantra 2000. The issue is intermittent. In the last year, we had the issu several times but after trying and trying, the engine would always finally start.
But 2 days ago, we were unable to start the engine. All the normal noise was there when we turn the ignition key but won<t start. I noticed that the IAC was making a buzzing noise (even when I had the keys removed from the ignition). What I finally did is unplug the IAC, tried to start the engine and this time it was different. The engine kind of started for a quarter second and stop. Did that a couple times. Plugged back the IAC cable. Turned the ignition key and it started like a new 2012 Elantra!

I am ready to buy and replace the IAC but after reading some sites, I have lost the 100% certitude that I have found the problem now I have some doubts that it might be a coincidence.

Does someone know if a bad IAC will prevent an engine to start or just cause problem when the engine is on idle^

Thanks in advance for you help.
Yves