There is a small foam filter inside the throttle body right where the hose is that goes back to the IAC. That filter can be sucked through the hose into the IAC causing failure. I replaced my IAC and audible alarm stopped, not sure if code stays stored or not. Easy to tell when IAC is bad. When IAC is good the huffing sound from throttle body while running will gradually go away once warmed up. When IAC goes bad that huffing/sucking sound will not go away.