hissssing noise 01 exc.

[1beav]

I have 01 exc. and it makes a hisssing noise when it is cold now.
It sits in a heated garage and when we go about 2 miles down the road it starts to make a hissssing noise when you go one speed and it don't matter what speed. As you speed up or slow down it goes away it's only when you mantain your speed, then about ten mile or so it just goes away, also when it kicks on fast idle it will make it. What could it be?

[Dave]

That sound is your Exhaust backpressure valve closing to air in engine warm up. As long as it goes away when warm its perfectly normal

[NCHornet]

EBPV and it is perfectly normal. We see lots of these posts when it gets cold out. Don't worry!!

[1beav]

If this is normanl y don't my f250 do it?

[Dave]

what year 250? Some trucks were not equipped with it. I know our 99 work truck doesnt have it

[1beav]

they are both 2001

[Dave]

Take a look at your turbo pedistal on the both trucks. If one does have the plug that is in the pic in the link below and the 250 doesnt. The 250 doesnt have the ebpv
Ebpv plug location pic wann make sure its the right one

[1beav]

this plug your talking about in the pic. Is it the black and orange with the little wire around it and is it unpluged out of the white hole above the blue thing.In the picture?

If it is yes both of them have it.

Boy lets use the technical words (white hole, blue thing)

[1beav]

So what will happen if I unplug mine?

[vitalidle]

If you unplug while the truck is off your valve will no longer close.