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[AkVolDaddy]

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ok so for the WHATS THAT SOUND. If it's coming from the tail pipe and sounds like someone has stuffed a potato up there, it's the Exhaust Back Pressure Valve (EBV). This valve closes in a cold engine to create a load which will help the engine warm up a little quicker.

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.

oh im duffy by the way new guy here ill do an introduction in anothe thread.

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The answer to your question I beleive lies more of when it is happening. Are you saying that you notice the sound when it is high idling? Mine does a pssst pssst cycle at the high idle as the wastgate gets rid of the uneeded boost while idling at higher rpms. It'll sound like its bouncing that wastegate a bunch...and its normal. Now if you are talking about when you are driving...again it depends on how you are driving. I don't get much waste when towing my boat...truck uses that power. But when I'm driving around town...it wasts a lot.