I'm having the same problem. We disassembled everything between the airfilter housing to the engine intake. It's in the intake. There's some kind of module, or sensor, with a black adjustment on it. (It's what I wanted to take a photo of, see earlier post.) When we opened the adjustment, the noise stopped. The engine won't run without it.
Hello,
> Wondering if anyone has a quick idea on this one. The noise (will be
> continuous....then turns to a "warbling" type ...spaced out sound...hard to
> describe...not a constant pitch...you would think its the belt...without the
> hi-end scream...but its not the belt) started occasionally....last
> summer(?..I think ?)....well...seemed to come up when hot outside.....so
> thought it was AC related.....but it will make this
weird...sound...without
the AC on...so not a belt...and dont think its the compressor...(wife thinks
> waterpump??..but temp has been fine).....
> I think its coming from under the intake??....so wonder if its an injector
> going bad??....but it will be fine first thing in the morning....and all day if
> not too hot out(maybe just coincidence on the heat)....really has me baffled.
> Other thing....on the side of the top intake housing....there is something that
> seems to be a black "knob" of sorts....for some sort of adjustment for..I dont
> know what...??...or a cover to a gauge or valve for something???.....maybe
> totally wrong?...anyway.....my Check Engine Light came on recently after the
> latest bout of the noise...and stays on now.......but Im wondering if thats
> just because I un-hooked the wire to the aforementioned "knob" box on side of
> intake.....thinking it was loose...it wasnt!!...
> ...so....what to do now......and the truck runs fine too by the
way....other
than what doesnt seem to be great gas mileage.....17 or so....mostly side road
> driving everyday...?
> .Any advice is appreciated....
> Thanks!
> Steve
> ....and please email me directly if possible ....I dont get on here much....
> snipped-for-privacy@aol.com
>