Fog (or Air) Horn Sound [Video Added] [SOLVED]

[DaytonGuy]

Truck started making an odd, intermittent fog horn like sound from under the hood. It's getting louder and more frequent. I initially suspected an idler pulley bearing or something like that. Further research online suggest there may be an issue with the Idle Air Control Valve. Has anyone had this problem on the V8 motor? I've seen videos of "how to clean the IAC on a ford", but are they all the same? Does cleaning work?

Here a link to a video of the noise.



Just trying to see what experiences others have had with this issue.

Thanks,

Chris

 

[DaytonGuy]

I changed out the upper left idler pulley and that seemed to do the trick.