I'll get Morris and some others who heard it at SL to chime in. (I think Demon was in my truck when it was doing it tbh)

My Airbox or Throttle body or something in that area howls. its loud, obnoxious and can be heard from a long distance away.

It only does it under a few conditions. It has to be hot (outside temperature wise). It will usually do it once it gets close to 90* F.
It will go away once you give it some RPMs. it will howl with anything under 1200-1400 RPMs. anything higher than that it it gets quieter until its non-exsitant.
If its howling, you can open the hood and feel the airbox vibrate. It used to be all i had to do was give the airbox and Intake hose a wiggle and smack, but that seems useless now.

It started this when i first got it and i did the Airbox Mod, shortly after i cleaned up the Airbox, Intake, Hose and Throttle body. which made it go away for about 2 weeks. Now it does it as stated above.

I don't want to waste any money on a Cold Air Intake, since its worthless, but if it gets rid of the howl i will. I can't put the silencer back in the air box either to see if thats it, because i ripped the cone apart pulling it out.

I can probably get a whole new setup from the JY, but i don't want to if this can be fixed.

I'll get a video of it if it starts doing it again. I've been trying for a few days, but it hasn't howled.

Thoughts/Suggestions/This trucks a piece of junk comments welcome.

 

I've had this on an OHV 4.0. Found it was the IAC "valve" vibrating causing the howl. Replaced IAC went away.