whining intake noise

I'm not real sure what a 'whistling throttle body' sounds like. I may have one.
The intake and tb are from a '99 explorer. The tb is mounted directly to the intake with no spacer. I also halfshafted the tb.

When first installed there was no noise. A week later there was a whistle at idle when cold. Then it started lasting longer and whining for a 1/2 mile while warming up. Sounds like a blower. Once warm the noise went away.

Last week I smoothed the iac hole and retorqued the intake. The noise changed. The cold whistle only lasted a few seconds but the whining noise is still there for a minute.

This noise is definitely from the intake. I removed the belt and the cai and the noise was still there. Removed the iac blocked the hole and the noise was still there. I'm using felpro graphite gaskets. The lower is ported to match the gt40p heads for the new motor sitting on a stand. I'm stumped on how to fix this other than removing the intake and making sure it isn't warped anywhere when the new motor goes in.

Anyone have any ideas?

Yeah, all the hoses hooked up proper and good condition. The pcv goes in the plenum twice with a T like factory. The canister line hooks to the pcv valve. The vacuum ports in the plenum have pipe plugs except the pcv. I drilled and tapped a hole for the brake booster/ pressure regulator vacuum in the plenum right past the tb. Pinching off hoses makes no difference. With the intake tube off and maf unplugged so she'll run the noise is still there. This thing sounds like a freakin' gear drive for the first mile when cold. I even thought my TCI converter was shelling for a minute. It is definitely up top though.

Torquing the intake again seems the best option. The sound changing with temp makes me think gasket leak. Carb spray makes no change at all though. Since it still made the noise with no iac it's hard to blame that. I can try a few different iac motors also. The original iac wouldnt bolt up right and idled 3000 rpm installed backwards. The one I'm using is from a 4.6 I think or maybe from the explorer motor. LoL I have a pile of used ones at work, but none from a fox 5.0.

Hmmm - I did make the tb gasket from some thick gasket material. It doesn't leak at all, according to the carb spray. There may be a small flap overhanging or something. Maybe I should buy a proper gasket

The whistling noise is gone, but the whining going down the road is louder now. My 10" tci converter tossed a fin or something. It's all General Motors fault for making cheap crap converters that can be modified to make a Ford faster and my fault for buying one. Oh well, sounds like a good excuse to rip the original motor out for the new one. Too bad my sister's father-in-law sold his converter shop