Experiencing this strange howling/whisling noise (the kind you hear if the wind is blowing through a small crack) but its NOT road noise. It happens when I hit the gas pedal (and its intermittant). If I let off the gas it goes away, if I touch the gas pedal again it comes back but it does not always do this. It is definately related to touching the bas pedal. I can not tell wherer the sound is coming from. Truck runs fine otherwise (expect for a very low idle that mechanic feels is just an innacurate RPM gauge and it idles fine).
Anyone experience this? I found nothing similiar when searching. thanks
ps, have the 4.7 engine with 56k miles. 4x4.

 

Sounds like a small vacuum leak. Maybe a bad seal where the resonator meets the throttlebody.

 

thanks...now that I think of it I believe this noise started after the mechanic replaced the Idle air control valve. I wonder if that is not seated properly but also wonder why it would be intermittant. I think it would always make that noise....but something to look into..