Loud whistle at part throttle after hard run

[Bootbox]

Hey guys :beer: hoping for a little insight into what may have happened this morning to my truck maybe some advice on how to proceed.

I was merging onto the highway and I got into it real good to get up to speed and right after I let out the truck starts making a train whistle sort of noise, it's constant whenever I'm on the gas just a little or when the revs are coming down while stopping. It's running rough at idle too.

I looked around the and can't find a leak in the easy to find spots so I figure it's got to be that damn hose at the back of the engine/lower intake manifold. It builds boost fine and the noise goes away when I get on the gas a little more than cruising but damn when the noise is there it's LOUD. It's embarassing to drive like this honestly.

The big question: Should I order a new IAC to lower intake manifold hose or take the opportunity to eliminate the PCV system?

Any tips on what to buy at local auto parts stores (name brands/part numbers) to eliminate the PCV system? I know I need two little filters on some heater hose for the valve covers and a few places need to be capped off but where do I cap off and what are the caps called? Are the caps hard to find in the right size? How do I get the heater hose that the filters are clamped on to not fall out of the valve covers? Do I just jam the hose in the PCV valve grommet or are people using a length of hardline to adapt at the grommet point?

Any advice/help here would be great. I know there are some how-tos on this but I figured I'd pick your brains, maybe there's updated info part #s?

 

[M240Bravo]

Blower whine? hahaha

I don't know.

 

[SID297]

The how-to posting here is going to be your best bet. Like most things you can use it as a jumping off point if you find a part that would look or function better. I'm not a huge fan of the PCV delete because of the added smell it introduces.

As for your noise, I'd check the bypass valve. If it is malfunctioning or obstructed it can make a bit of noise.

 

[galightning2000]

Perhaps the Intake Air Temperature Sensor which plugs into the air cleaner box. I had the same issue with the noise and it drove me nuts. Once you replace it, it will continue to make the noise until the computer learns it. Just drive it for about 10 minutes until the noise goes away. Make sure you disconnect the negative cable from the battery before you replace it. It should cost about $25 and it takes about 2 minutes to replace. Let me know if this works for you. Hope this helps.

 

[Robert Francis]

The "how to's" and searching on here can give you all kind sof info on eleminating your PCV system.

I suppose it could be that elbow down there on the lower intake, that perhaps is split and is making the sound you describe - but if you do a search on here, I think you'll many have a bad elbow down there - but didn't have the sound you describe.

In addition to what yopu have already sought out for leaks, I'd suggest checking your throttle body to plenum gasket for leaking.

 

[SKIP 56]

I'm having this same noise. Truck runs great. I replaced the lower intake elbow but its still doing it. Did you ever figure yours out? If so let me know. Any other help would be great.