Whistle under the hood

[007.3Powerstroke]

So let me see if i can explain this in writing...

The other day i noticed a Whistle type noise from my truck after i let off the gas and it also does it if i give it gas. its not really loud but enough i can hear it in the cab. Any one ever had this happen? The truck doesnt run any different or miss or anything eles that is making me think its going to blow up or something. Just want to see if anyone has had this happen. I want to get it fixed before riding season comes along and i start pulling trailers all over to go ride.

Thanks

and its a 04 with sct tuned and 4in from the turbo back.

[007.3Powerstroke]

after doing some reading some are saying it Coolant Bottle Cap

[Young-SC-Owner]

Yeah degas bottle cap, is it a motor craft cap?

I put a brand new fomoco cap on and it puked from day one. I went and got an aftermarket


Sent from my iPhone using AutoGuide.com App

[007.3Powerstroke]

yea its the stock cap.

[dth0mas]

Is your eot ect normal?

[southend]

Could be this, read on down....fords doing my studs( pics )

Sent from my phone that somebody didn't help me get.

[T diesel]

Had the same whistle.
Leaking head gaskets for me.

[007.3Powerstroke]

i hope its not that! im going to get them done but not until my tax money comes in.

[007.3Powerstroke]

Ive also noticed that it only does it after the truck has warmed all the way up. I need to go find a new cap and see if that its or not i guess.

[007.3Powerstroke]

Ok so to fix this do i need to get a cap form ford or is this something i can get from a atuo parts store?