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[GI_Joe]

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my sound isnt coming from the tail pipe it sounds like pssssssssssssssst and will go away at say 3/4 throttle, and it feels like its holding up the truck in tems of performance. i had initally thought a waste gate was stuck open then i got to thinking more that maybe it was something ford did to help the turbo/motor in cold conditions cuz it did it one day in 30 deg but then the next morn it was like 50 and it didnt do it. so i hope thats what it is.

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I'm with Duffy. I am also hearing a pssssssst sound, more often in cold temps, but not extremely cold - Usually around 30F and below. It is more noticeable the colder it gets. Generally when I'm coasting but just hitting the throttle enough to maintain about 25mph on a level road. If I throttle up it goes away and if I idle it goes away. I thought it might be something from the turbo, but I have no idea. It does seem to hinder performance, though. I still hear it even after the engine reaches operating temp.

By the way, I'm also new to this forum. I'm glad someone told me about this because I'm having cold start problems, too. I think you all answered all my questions about that. Thanks!!

Joe